diff --git a/src/lib/Client/DaprClient.php b/src/lib/Client/DaprClient.php
index f0834dd..5d58d1b 100644
--- a/src/lib/Client/DaprClient.php
+++ b/src/lib/Client/DaprClient.php
@@ -385,7 +385,7 @@ abstract public function deleteState(
     /**
      * @param string $storeName
      * @param string $key
-     * @param string $etag
+     * @param string|null $etag
      * @param Consistency|null $consistency
      * @param array<array-key, string> $metadata
      * @return PromiseInterface<bool>
@@ -393,7 +393,7 @@ abstract public function deleteState(
     abstract public function tryDeleteStateAsync(
         string $storeName,
         string $key,
-        string $etag,
+        string|null $etag,
         Consistency|null $consistency = null,
         array $metadata = []
     ): PromiseInterface;
@@ -401,7 +401,7 @@ abstract public function tryDeleteStateAsync(
     /**
      * @param string $storeName
      * @param string $key
-     * @param string $etag
+     * @param string|null $etag
      * @param Consistency|null $consistency
      * @param array<array-key, string> $metadata
      * @return bool
@@ -409,7 +409,7 @@ abstract public function tryDeleteStateAsync(
     abstract public function tryDeleteState(
         string $storeName,
         string $key,
-        string $etag,
+        string|null $etag,
         Consistency|null $consistency = null,
         array $metadata = []
     ): bool;
diff --git a/src/lib/Client/HttpStateTrait.php b/src/lib/Client/HttpStateTrait.php
index 9243797..2c2e926 100644
--- a/src/lib/Client/HttpStateTrait.php
+++ b/src/lib/Client/HttpStateTrait.php
@@ -237,7 +237,7 @@ public function deleteStateAsync(
     public function tryDeleteStateAsync(
         string $storeName,
         string $key,
-        string $etag,
+        string|null $etag,
         Consistency|null $consistency = null,
         array $metadata = []
     ): PromiseInterface {
@@ -269,7 +269,7 @@ public function tryDeleteStateAsync(
     public function tryDeleteState(
         string $storeName,
         string $key,
-        string $etag,
+        string|null $etag,
         Consistency|null $consistency = null,
         array $metadata = []
     ): bool {
diff --git a/tests/DeleteStateTest.php b/tests/DeleteStateTest.php
new file mode 100644
index 0000000..b41ff23
--- /dev/null
+++ b/tests/DeleteStateTest.php
@@ -0,0 +1,37 @@
+<?php
+
+use GuzzleHttp\Psr7\Response;
+
+require_once __DIR__ . '/DaprTests.php';
+
+/**
+ * Class DeleteStateTest
+ */
+class DeleteStateTest extends DaprTests
+{
+    public function testDeleteStateWithoutEtag(): void
+    {
+        $stack = $this->get_http_client_stack([new Response(204)]);
+        $client = $this->get_new_client_with_http($stack->client);
+
+        $client->deleteState(storeName: 'store', key: 'key');
+
+        $request = $this->get_last_request($stack);
+        $this->assertRequestMethod('DELETE', $request);
+        $this->assertRequestUri('/v1.0/state/store/key', $request);
+        $this->assertFalse($request->hasHeader('If-Match'));
+    }
+
+    public function testTryDeleteStateWithEtag(): void
+    {
+        $stack = $this->get_http_client_stack([new Response(204)]);
+        $client = $this->get_new_client_with_http($stack->client);
+
+        $client->tryDeleteState(storeName: 'store', key: 'key', etag: 'abc123');
+
+        $request = $this->get_last_request($stack);
+        $this->assertRequestMethod('DELETE', $request);
+        $this->assertRequestUri('/v1.0/state/store/key', $request);
+        $this->assertRequestHasHeaders(['If-Match' => 'abc123'], $request);
+    }
+}