diff --git a/clients/line-bot-manage-audience-client/src/test/java/com/linecorp/bot/audience/client/ManageAudienceBlobClientExTest.java b/clients/line-bot-manage-audience-client/src/test/java/com/linecorp/bot/audience/client/ManageAudienceBlobClientExTest.java
new file mode 100644
index 000000000..f3d8f6d0a
--- /dev/null
+++ b/clients/line-bot-manage-audience-client/src/test/java/com/linecorp/bot/audience/client/ManageAudienceBlobClientExTest.java
@@ -0,0 +1,96 @@
+/*
+ * Copyright 2023 LINE Corporation
+ *
+ * LINE Corporation licenses this file to you under the Apache License,
+ * version 2.0 (the "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at:
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ */
+
+package com.linecorp.bot.audience.client;
+
+import static com.github.tomakehurst.wiremock.client.WireMock.aMultipart;
+import static com.github.tomakehurst.wiremock.client.WireMock.aResponse;
+import static com.github.tomakehurst.wiremock.client.WireMock.configureFor;
+import static com.github.tomakehurst.wiremock.client.WireMock.containing;
+import static com.github.tomakehurst.wiremock.client.WireMock.equalTo;
+import static com.github.tomakehurst.wiremock.client.WireMock.put;
+import static com.github.tomakehurst.wiremock.client.WireMock.putRequestedFor;
+import static com.github.tomakehurst.wiremock.client.WireMock.stubFor;
+import static com.github.tomakehurst.wiremock.client.WireMock.urlEqualTo;
+import static com.github.tomakehurst.wiremock.client.WireMock.verify;
+import static com.github.tomakehurst.wiremock.core.WireMockConfiguration.wireMockConfig;
+
+import java.net.URI;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Timeout;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.slf4j.bridge.SLF4JBridgeHandler;
+
+import com.github.tomakehurst.wiremock.WireMockServer;
+
+import com.linecorp.bot.client.base.UploadFile;
+
+@ExtendWith(MockitoExtension.class)
+@Timeout(5)
+public class ManageAudienceBlobClientExTest {
+    static {
+        SLF4JBridgeHandler.removeHandlersForRootLogger();
+        SLF4JBridgeHandler.install();
+    }
+
+    private WireMockServer wireMockServer;
+    private ManageAudienceBlobClient target;
+
+    @BeforeEach
+    public void setUp() {
+        wireMockServer = new WireMockServer(wireMockConfig().dynamicPort());
+        wireMockServer.start();
+        configureFor("localhost", wireMockServer.port());
+
+        target = ManageAudienceBlobClient.builder("MY_OWN_TOKEN")
+                .apiEndPoint(URI.create(wireMockServer.baseUrl()))
+                .build();
+    }
+
+    @AfterEach
+    public void tearDown() {
+        wireMockServer.stop();
+    }
+
+    @Test
+    public void testAddUserIdsToAudience() {
+        stubFor(put(urlEqualTo("/v2/bot/audienceGroup/upload/byFile"))
+                .withMultipartRequestBody(aMultipart()
+                        .withName("file")
+                        .withBody(equalTo("foobar"))
+                        .withHeader("Content-Disposition", containing("filename=\"file\""))
+                ).willReturn(
+                aResponse()
+                        .withStatus(200)
+                        .withHeader("content-type", "application/json")
+                        .withBody("{}")));
+
+        // Do
+        target.addUserIdsToAudience(4649L, "Hello", UploadFile.fromString("foobar", "text/plain"))
+                .join();
+
+        // Verify
+        verify(
+                putRequestedFor(
+                        urlEqualTo("/v2/bot/audienceGroup/upload/byFile")
+                ).withHeader("Authorization", equalTo("Bearer MY_OWN_TOKEN"))
+        );
+    }
+}
diff --git a/templates/libraries/retrofit2/formParams.mustache b/templates/libraries/retrofit2/formParams.mustache
index 6f6100353..081ace972 100644
--- a/templates/libraries/retrofit2/formParams.mustache
+++ b/templates/libraries/retrofit2/formParams.mustache
@@ -1,4 +1,4 @@
 {{#isFormParam}}
     {{^isFile}}{{#isMultipart}}@Part{{/isMultipart}}{{^isMultipart}}@Field{{/isMultipart}}("{{baseName}}") {{{dataType}}} {{paramName}}{{/isFile}}
-    {{#isFile}}{{#isMultipart}}@Part("{{baseName}}"){{/isMultipart}}{{^isMultipart}}@Field("{{baseName}}"){{/isMultipart}} UploadFile {{paramName}}{{/isFile}}
+    {{#isFile}}{{#isMultipart}}@Part("{{baseName}}\"; filename=\"{{baseName}}"){{/isMultipart}}{{^isMultipart}}@Field("{{baseName}}"){{/isMultipart}} UploadFile {{paramName}}{{/isFile}}
 {{/isFormParam}}