diff --git a/backend/posix/posix.go b/backend/posix/posix.go
index cebfa45..ae2a715 100644
--- a/backend/posix/posix.go
+++ b/backend/posix/posix.go
@@ -223,6 +223,12 @@ func (p *Posix) CreateMultipartUpload(_ context.Context, mpu *s3.CreateMultipart
 		return nil, fmt.Errorf("stat bucket: %w", err)
 	}
 
+	if strings.HasSuffix(*mpu.Key, "/") {
+		// directory objects can't be uploaded with mutlipart uploads
+		// because posix directories can't contain data
+		return nil, s3err.GetAPIError(s3err.ErrDirectoryObjectContainsData)
+	}
+
 	// generate random uuid for upload id
 	uploadID := uuid.New().String()
 	// hash object name for multipart container
@@ -960,6 +966,13 @@ func (p *Posix) PutObject(ctx context.Context, po *s3.PutObjectInput) (string, e
 
 	if strings.HasSuffix(*po.Key, "/") {
 		// object is directory
+		if po.ContentLength != 0 {
+			// posix directories can't contain data, send error
+			// if reuests has a data payload associated with a
+			// directory object
+			return "", s3err.GetAPIError(s3err.ErrDirectoryObjectContainsData)
+		}
+
 		err = mkdirAll(name, os.FileMode(0755), *po.Bucket, *po.Key)
 		if err != nil {
 			return "", err
diff --git a/s3err/s3err.go b/s3err/s3err.go
index 82e791f..838ee0f 100644
--- a/s3err/s3err.go
+++ b/s3err/s3err.go
@@ -115,6 +115,7 @@ const (
 	// Non-AWS errors
 	ErrExistingObjectIsDirectory
 	ErrObjectParentIsFile
+	ErrDirectoryObjectContainsData
 )
 
 var errorCodeResponse = map[ErrorCode]APIError{
@@ -408,6 +409,11 @@ var errorCodeResponse = map[ErrorCode]APIError{
 		Description:    "Object parent already exists as a file.",
 		HTTPStatusCode: http.StatusConflict,
 	},
+	ErrDirectoryObjectContainsData: {
+		Code:           "DirectoryObjectContainsData",
+		Description:    "Directory object contains data payload.",
+		HTTPStatusCode: http.StatusBadRequest,
+	},
 }
 
 // GetAPIError provides API Error for input API error code.