diff --git a/src/activitypub/actors/attachments.rs b/src/activitypub/actors/attachments.rs
index b7e5b72..f498b99 100644
--- a/src/activitypub/actors/attachments.rs
+++ b/src/activitypub/actors/attachments.rs
@@ -47,7 +47,10 @@ pub fn parse_identity_proof(
     };
     let did = attachment.name.parse::<Did>()
         .map_err(|_| ValidationError("invalid did"))?;
-    let Did::Pkh(ref did_pkh) = did;
+    let did_pkh = match did {
+        Did::Pkh(ref did_pkh) => did_pkh,
+        _ => return Err(ValidationError("invalid proof issuer")),
+    };
     let signature = attachment.signature_value.as_ref()
         .ok_or(ValidationError("missing signature"))?;
     verify_eip191_identity_proof(
diff --git a/src/identity/did.rs b/src/identity/did.rs
index 4e14a0f..7a8e166 100644
--- a/src/identity/did.rs
+++ b/src/identity/did.rs
@@ -8,12 +8,14 @@ use serde::{
     de::Error as DeserializerError,
 };
 
+use super::did_key::DidKey;
 use super::did_pkh::DidPkh;
 
 const DID_RE: &str = r"did:(?P<method>\w+):.+";
 
 #[derive(Clone, Debug, PartialEq)]
 pub enum Did {
+    Key(DidKey),
     Pkh(DidPkh),
 }
 
@@ -28,6 +30,10 @@ impl FromStr for Did {
         let did_re = Regex::new(DID_RE).unwrap();
         let caps = did_re.captures(value).ok_or(DidParseError)?;
         let did = match &caps["method"] {
+            "key" => {
+                let did_key = DidKey::from_str(value)?;
+                Self::Key(did_key)
+            },
             "pkh" => {
                 let did_pkh = DidPkh::from_str(value)?;
                 Self::Pkh(did_pkh)
@@ -41,6 +47,7 @@ impl FromStr for Did {
 impl fmt::Display for Did {
     fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
         let did_str = match self {
+            Self::Key(did_key) => did_key.to_string(),
             Self::Pkh(did_pkh) => did_pkh.to_string(),
         };
         write!(formatter, "{}", did_str)
diff --git a/src/identity/did_key.rs b/src/identity/did_key.rs
new file mode 100644
index 0000000..8cee6d5
--- /dev/null
+++ b/src/identity/did_key.rs
@@ -0,0 +1,46 @@
+/// https://w3c-ccg.github.io/did-method-key/
+use std::fmt;
+use std::str::FromStr;
+
+use regex::Regex;
+
+use super::did::DidParseError;
+
+const DID_KEY_RE: &str = r"did:key:(?P<key>z[a-km-zA-HJ-NP-Z1-9]+)";
+
+#[derive(Clone, Debug, PartialEq)]
+pub struct DidKey {
+    pub key: String,
+}
+
+impl FromStr for DidKey {
+    type Err = DidParseError;
+
+    fn from_str(value: &str) -> Result<Self, Self::Err> {
+        let did_key_re = Regex::new(DID_KEY_RE).unwrap();
+        let caps = did_key_re.captures(value).ok_or(DidParseError)?;
+        let did_key = Self {
+            key: caps["key"].to_string(),
+        };
+        Ok(did_key)
+    }
+}
+
+impl fmt::Display for DidKey {
+    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let did_str = format!("did:key:{}", self.key);
+        write!(formatter, "{}", did_str)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_did_key_string_conversion() {
+        let did_str = "did:key:z6MkhaXgBZDvotDkL5257faiztiGiC2QtKLGpbnnEGta2doK";
+        let did_key: DidKey = did_str.parse().unwrap();
+        assert_eq!(did_key.to_string(), did_str);
+    }
+}
diff --git a/src/identity/did_pkh.rs b/src/identity/did_pkh.rs
index f3e42c7..66d20ef 100644
--- a/src/identity/did_pkh.rs
+++ b/src/identity/did_pkh.rs
@@ -49,14 +49,14 @@ impl FromStr for DidPkh {
     fn from_str(value: &str) -> Result<Self, Self::Err> {
         let did_pkh_re = Regex::new(DID_PKH_RE).unwrap();
         let caps = did_pkh_re.captures(value).ok_or(DidParseError)?;
-        let did = Self {
+        let did_pkh = Self {
             chain_id: ChainId {
                 namespace: caps["network"].to_string(),
                 reference: caps["chain"].to_string(),
             },
             address: caps["address"].to_string(),
         };
-        Ok(did)
+        Ok(did_pkh)
     }
 }
 
diff --git a/src/identity/mod.rs b/src/identity/mod.rs
index 71660b9..42499cf 100644
--- a/src/identity/mod.rs
+++ b/src/identity/mod.rs
@@ -1,2 +1,3 @@
 pub mod did;
+pub mod did_key;
 pub mod did_pkh;
diff --git a/src/mastodon_api/accounts/types.rs b/src/mastodon_api/accounts/types.rs
index 4292cf9..c2e9d0b 100644
--- a/src/mastodon_api/accounts/types.rs
+++ b/src/mastodon_api/accounts/types.rs
@@ -79,7 +79,10 @@ impl Account {
 
         let mut identity_proofs = vec![];
         for proof in profile.identity_proofs.clone().into_inner() {
-            let Did::Pkh(did_pkh) = proof.issuer;
+            let did_pkh = match proof.issuer {
+                Did::Pkh(did_pkh) => did_pkh,
+                _ => continue,
+            };
             // Skip proof if it doesn't map to field name
             if let Some(currency) = did_pkh.currency() {
                 let field_name = currency.field_name();
diff --git a/src/mastodon_api/accounts/views.rs b/src/mastodon_api/accounts/views.rs
index 7245915..daad253 100644
--- a/src/mastodon_api/accounts/views.rs
+++ b/src/mastodon_api/accounts/views.rs
@@ -261,10 +261,14 @@ async fn send_signed_update(
     ).map_err(|_| HttpError::InternalError)?;
     let canonical_json = canonicalize_object(&activity)
         .map_err(|_| HttpError::InternalError)?;
-    let Did::Pkh(signer) = signer;
-    verify_jcs_eip191_signature(&signer, &canonical_json, &data.signature)
-        .map_err(|_| ValidationError("invalid signature"))?;
-    let proof = IntegrityProof::jcs_eip191(&signer, &data.signature);
+    let proof = match signer {
+        Did::Key(_) => return Err(ValidationError("unsupported DID type").into()),
+        Did::Pkh(signer) => {
+            verify_jcs_eip191_signature(&signer, &canonical_json, &data.signature)
+                .map_err(|_| ValidationError("invalid signature"))?;
+            IntegrityProof::jcs_eip191(&signer, &data.signature)
+        },
+    };
     let mut activity_value = serde_json::to_value(activity)
         .map_err(|_| HttpError::InternalError)?;
     add_integrity_proof(&mut activity_value, proof)
@@ -291,8 +295,12 @@ async fn get_identity_claim(
     let db_client = &**get_database_client(&db_pool).await?;
     let current_user = get_current_user(db_client, auth.token()).await?;
     let actor_id = current_user.profile.actor_id(&config.instance_url());
-    let Did::Pkh(did) = query_params.did.parse::<Did>()
+    let did = query_params.did.parse::<Did>()
         .map_err(|_| ValidationError("invalid DID"))?;
+    let did = match did {
+        Did::Key(_) => return Err(ValidationError("unsupported DID type").into()),
+        Did::Pkh(did_pkh) => did_pkh,
+    };
     let claim = create_identity_claim(&actor_id, &did)
         .map_err(|_| HttpError::InternalError)?;
     let response = IdentityClaim { claim };
@@ -311,7 +319,10 @@ async fn create_identity_proof(
     let actor_id = current_user.profile.actor_id(&config.instance_url());
     let did = proof_data.did.parse::<Did>()
         .map_err(|_| ValidationError("invalid DID"))?;
-    let Did::Pkh(ref did_pkh) = did;
+    let did_pkh = match did {
+        Did::Key(_) => return Err(ValidationError("unsupported DID type").into()),
+        Did::Pkh(ref did_pkh) => did_pkh,
+    };
     if did_pkh.chain_id != ChainId::ethereum_mainnet() {
         // DID must point to Ethereum Mainnet because it is a valid
         // identifier on any Ethereum chain
diff --git a/src/models/profiles/queries.rs b/src/models/profiles/queries.rs
index f30acad..2486d7b 100644
--- a/src/models/profiles/queries.rs
+++ b/src/models/profiles/queries.rs
@@ -434,6 +434,7 @@ pub async fn search_profiles_by_did(
             did_pkh.currency()
                 .map(|currency| (currency, did_pkh.address.clone()))
         },
+        _ => None,
     };
     let unverified = if let Some((currency, address)) = maybe_currency_address {
         // If currency is Ethereum,
diff --git a/src/models/profiles/types.rs b/src/models/profiles/types.rs
index 5913994..6617694 100644
--- a/src/models/profiles/types.rs
+++ b/src/models/profiles/types.rs
@@ -430,7 +430,10 @@ mod tests {
     fn test_identity_proof_serialization() {
         let json_data = r#"{"issuer":"did:pkh:eip155:1:0xb9c5714089478a327f09197987f16f9e5d936e8a","proof_type":"ethereum-eip191-00","value":"dbfe"}"#;
         let proof: IdentityProof = serde_json::from_str(json_data).unwrap();
-        let Did::Pkh(ref did_pkh) = proof.issuer;
+        let did_pkh = match proof.issuer {
+            Did::Pkh(ref did_pkh) => did_pkh,
+            _ => panic!("unexpected did method"),
+        };
         assert_eq!(did_pkh.address, "0xb9c5714089478a327f09197987f16f9e5d936e8a");
         let serialized = serde_json::to_string(&proof).unwrap();
         assert_eq!(serialized, json_data);
diff --git a/src/models/users/types.rs b/src/models/users/types.rs
index 0d316f8..db95f89 100644
--- a/src/models/users/types.rs
+++ b/src/models/users/types.rs
@@ -49,7 +49,10 @@ impl User {
     /// Returns wallet address if it is verified
     pub fn public_wallet_address(&self, currency: &Currency) -> Option<String> {
         for proof in self.profile.identity_proofs.clone().into_inner() {
-            let Did::Pkh(did_pkh) = proof.issuer;
+            let did_pkh = match proof.issuer {
+                Did::Pkh(did_pkh) => did_pkh,
+                _ => continue,
+            };
             // Return the first matching address, because only
             // one proof per currency is allowed.
             if let Some(ref address_currency) = did_pkh.currency() {