diff --git a/meilisearch-core/src/store/synonyms.rs b/meilisearch-core/src/store/synonyms.rs
index bf7472f96..31d4bb10f 100644
--- a/meilisearch-core/src/store/synonyms.rs
+++ b/meilisearch-core/src/store/synonyms.rs
@@ -12,18 +12,14 @@ pub struct Synonyms {
 }
 
 impl Synonyms {
-    pub fn put_synonyms<A>(self, writer: &mut heed::RwTxn<MainT>, word: &[u8], synonyms: &fst::Set<A>) -> ZResult<()>
+    pub(crate) fn put_synonyms<A>(self, writer: &mut heed::RwTxn<MainT>, word: &[u8], synonyms: &fst::Set<A>) -> ZResult<()>
     where A: AsRef<[u8]>,
     {
         let bytes = synonyms.as_fst().as_bytes();
         self.synonyms.put(writer, word, bytes)
     }
 
-    pub fn del_synonyms(self, writer: &mut heed::RwTxn<MainT>, word: &[u8]) -> ZResult<bool> {
-        self.synonyms.delete(writer, word)
-    }
-
-    pub fn clear(self, writer: &mut heed::RwTxn<MainT>) -> ZResult<()> {
+    pub(crate) fn clear(self, writer: &mut heed::RwTxn<MainT>) -> ZResult<()> {
         self.synonyms.clear(writer)
     }
 
diff --git a/meilisearch-core/src/update/settings_update.rs b/meilisearch-core/src/update/settings_update.rs
index 94e337265..7fa0f983c 100644
--- a/meilisearch-core/src/update/settings_update.rs
+++ b/meilisearch-core/src/update/settings_update.rs
@@ -126,7 +126,7 @@ pub fn apply_settings_update(
     }
 
     match settings.synonyms {
-        UpdateState::Update(synonyms) => apply_synonyms_update(writer, index, synonyms)?,
+        UpdateState::Update(synonyms) => apply_synonyms_update(writer, index, canonicalize_synonyms(synonyms))? ,
         UpdateState::Clear => apply_synonyms_update(writer, index, BTreeMap::new())?,
         UpdateState::Nothing => (),
     }
@@ -138,6 +138,18 @@ pub fn apply_settings_update(
     Ok(())
 }
 
+fn canonicalize_synonyms(synonyms: BTreeMap<String, Vec<String>>) -> BTreeMap<String, Vec<String>> {
+    let mut canonicalized = BTreeMap::new();
+    for (key, values) in synonyms {
+        let deunicoded = deunicode::deunicode(&key);
+        canonicalized
+            .entry(deunicoded)
+            .or_insert_with(Vec::new)
+            .extend_from_slice(&values);
+    }
+    canonicalized
+}
+
 fn apply_attributes_for_faceting_update(
     writer: &mut heed::RwTxn<MainT>,
     index: &store::Index,
diff --git a/meilisearch-http/tests/search.rs b/meilisearch-http/tests/search.rs
index 92879bb7b..f4ce60219 100644
--- a/meilisearch-http/tests/search.rs
+++ b/meilisearch-http/tests/search.rs
@@ -1829,3 +1829,38 @@ async fn update_documents_with_facet_distribution() {
     let (response2, _) = server.search_post(search).await;
     assert_json_eq!(expected_facet_distribution, response2["facetsDistribution"].clone());
 }
+
+#[actix_rt::test]
+async fn test_search_synonyms_unicased() {
+    let mut server = common::Server::with_uid("test");
+    let body = json!({ "uid": "test" });
+    server.create_index(body).await;
+    let settings = json!({
+        "synonyms": {
+            "cáse": ["truc"],
+            "case": ["machin"]
+        }
+    });
+    server.update_all_settings(settings).await;
+
+    let (response, _) = server.get_synonyms().await;
+    assert_json_eq!(response, json!({"case":["machin", "truc"]}));
+
+    let update = json!([
+        {
+            "id": "1",
+            "title": "truc"
+        },
+    ]);
+    server.add_or_update_multiple_documents(update).await;
+
+    let search = json!({
+        "q": "case",
+    });
+    let (response, _) = server.search_post(search).await;
+    assert_eq!(response["hits"].as_array().unwrap().len(), 1);
+
+    server.delete_synonyms().await;
+    let (response, _) = server.get_synonyms().await;
+    assert_json_eq!(response, json!({}));
+}