diff --git a/slack-api-client/src/main/java/com/slack/api/methods/impl/MethodsClientImpl.java b/slack-api-client/src/main/java/com/slack/api/methods/impl/MethodsClientImpl.java
index 18f35c8c3..a51c9c287 100644
--- a/slack-api-client/src/main/java/com/slack/api/methods/impl/MethodsClientImpl.java
+++ b/slack-api-client/src/main/java/com/slack/api/methods/impl/MethodsClientImpl.java
@@ -2333,20 +2333,19 @@ public FilesUploadV2Response filesUploadV2(FilesUploadV2Request req) throws IOEx
             if (req.getUploadFiles() != null && req.getUploadFiles().size() > 0) {
                 // upload multiple files
                 for (FilesUploadV2Request.UploadFile uploadFile : req.getUploadFiles()) {
-                    if (uploadFile.getTitle() != null) {
-                        uploadFile.setTitle(uploadFile.getTitle());
-                    } else {
-                        String filename = req.getFilename();
-                        if (filename == null) {
-                            if (uploadFile.getFile() != null && uploadFile.getFile().getName() != null) {
-                                filename = uploadFile.getFile().getName();
-                            } else {
-                                filename = "Uploaded file";
-                            }
+                    String filename = uploadFile.getFilename();
+                    if (filename == null) {
+                        if (uploadFile.getFile() != null && uploadFile.getFile().getName() != null) {
+                            filename = uploadFile.getFile().getName();
+                        } else {
+                            filename = "Uploaded file";
                         }
-                        uploadFile.setFilename(filename);
+                    }
+                    uploadFile.setFilename(filename);
+                    if (uploadFile.getTitle() == null) {
                         uploadFile.setTitle(filename);
                     }
+
                     String fileId = helper.uploadFile(req, uploadFile);
 
                     FilesCompleteUploadExternalRequest.FileDetails file = new FilesCompleteUploadExternalRequest.FileDetails();
diff --git a/slack-api-client/src/test/java/test_with_remote_apis/methods/files_Test.java b/slack-api-client/src/test/java/test_with_remote_apis/methods/files_Test.java
index 96dcb6de6..a464e005c 100644
--- a/slack-api-client/src/test/java/test_with_remote_apis/methods/files_Test.java
+++ b/slack-api-client/src/test/java/test_with_remote_apis/methods/files_Test.java
@@ -1167,4 +1167,91 @@ public void filesUploadV2_manual_two_files() throws Exception {
         FilesInfoResponse file1info = client.filesInfo(r -> r.file(file1Upload.getFileId()));
         assertThat(file1info.getFile().getShares().getPublicChannels().get(randomChannelId), is(notNullValue()));
     }
+
+    @Test
+    public void issue1345_filesUploadV2_multiple() throws IOException, SlackApiException {
+        loadRandomChannelId();
+        MethodsClient slackMethods = slack.methods(userToken);
+
+        byte[] fileData = Files.readAllBytes(Paths.get("src/test/resources/sample.txt"));
+
+        // note: this test can be done using only one file as everything tested applies to each file individually - the only important thing is to use "uploadFiles" instead of direct values
+        FilesUploadV2Request.UploadFile uploadFile = FilesUploadV2Request.UploadFile.builder().filename("issue1345_test.txt").title("issue1345 test").fileData(fileData).build();
+        FilesUploadV2Response response = slackMethods.filesUploadV2(r -> r.uploadFiles(Arrays.asList(uploadFile)));
+
+        assertThat(response.getError(), is(nullValue()));
+        assertThat(response.getFiles().get(0).getName(), is("issue1345_test.txt"));
+        assertThat(response.getFiles().get(0).getTitle(), is("issue1345 test"));
+    }
+
+    @Test
+    public void issue1345_filesUploadV2_multiple_no_title() throws IOException, SlackApiException {
+        loadRandomChannelId();
+        MethodsClient slackMethods = slack.methods(userToken);
+
+        byte[] fileData = Files.readAllBytes(Paths.get("src/test/resources/sample.txt"));
+
+        // note: this test can be done using only one file as everything tested applies to each file individually - the only important thing is to use "uploadFiles" instead of direct values
+        FilesUploadV2Request.UploadFile uploadFile = FilesUploadV2Request.UploadFile.builder().filename("issue1345_test.txt").fileData(fileData).build();
+        FilesUploadV2Response response = slackMethods.filesUploadV2(r -> r.uploadFiles(Arrays.asList(uploadFile)));
+
+        assertThat(response.getError(), is(nullValue()));
+        assertThat(response.getFiles().get(0).getName(), is("issue1345_test.txt"));
+        // title should default to filename
+        assertThat(response.getFiles().get(0).getTitle(), is("issue1345_test.txt"));
+    }
+
+    @Test
+    public void issue1345_filesUploadV2_multiple_no_filename() throws IOException, SlackApiException {
+        loadRandomChannelId();
+        MethodsClient slackMethods = slack.methods(userToken);
+
+        byte[] fileData = Files.readAllBytes(Paths.get("src/test/resources/sample.txt"));
+
+        // note: this test can be done using only one file as everything tested applies to each file individually - the only important thing is to use "uploadFiles" instead of direct values
+        FilesUploadV2Request.UploadFile uploadFile = FilesUploadV2Request.UploadFile.builder().title("issue1345 test").fileData(fileData).build();
+        FilesUploadV2Response response = slackMethods.filesUploadV2(r -> r.uploadFiles(Arrays.asList(uploadFile)));
+
+        assertThat(response.getError(), is(nullValue()));
+        // filename defaults to "Uploaded file", which will be converted by slack servers to be lowercase only, contain no special characters but underscores, dots and dashes, etc.
+        assertThat(response.getFiles().get(0).getName(), is("uploaded_file"));
+        // title should be unaffected if it has a value set
+        assertThat(response.getFiles().get(0).getTitle(), is("issue1345 test"));
+    }
+
+    @Test
+    public void issue1345_filesUploadV2_multiple_no_filename_no_title_file() throws IOException, SlackApiException {
+        loadRandomChannelId();
+        MethodsClient slackMethods = slack.methods(userToken);
+
+        File file = new File("src/test/resources/sample.txt");
+
+        // note: this test can be done using only one file as everything tested applies to each file individually - the only important thing is to use "uploadFiles" instead of direct values
+        FilesUploadV2Request.UploadFile uploadFile = FilesUploadV2Request.UploadFile.builder().file(file).build();
+        FilesUploadV2Response response = slackMethods.filesUploadV2(r -> r.uploadFiles(Arrays.asList(uploadFile)));
+
+        assertThat(response.getError(), is(nullValue()));
+        // filename defaults to "Uploaded file", which will be converted by slack servers to be lowercase only, contain no special characters but underscores, dots and dashes, etc.
+        assertThat(response.getFiles().get(0).getName(), is("sample.txt"));
+        // title should be unaffected if it has a value set
+        assertThat(response.getFiles().get(0).getTitle(), is("sample.txt"));
+    }
+
+    @Test
+    public void issue1345_filesUploadV2_multiple_no_filename_no_title() throws IOException, SlackApiException {
+        loadRandomChannelId();
+        MethodsClient slackMethods = slack.methods(userToken);
+
+        byte[] fileData = Files.readAllBytes(Paths.get("src/test/resources/sample.txt"));
+
+        // note: this test can be done using only one file as everything tested applies to each file individually - the only important thing is to use "uploadFiles" instead of direct values
+        FilesUploadV2Request.UploadFile uploadFile = FilesUploadV2Request.UploadFile.builder().fileData(fileData).build();
+        FilesUploadV2Response response = slackMethods.filesUploadV2(r -> r.uploadFiles(Arrays.asList(uploadFile)));
+
+        assertThat(response.getError(), is(nullValue()));
+        // filename defaults to "Uploaded file", which will be converted by slack servers to be lowercase only, contain no special characters but underscores, dots and dashes, etc.
+        assertThat(response.getFiles().get(0).getName(), is("uploaded_file"));
+        // title defaults to filename, which is (as this is defaulted on the client side) "Uploaded file"
+        assertThat(response.getFiles().get(0).getTitle(), is("Uploaded file"));
+    }
 }