diff --git a/internal/llm/provider/gemini.go b/internal/llm/provider/gemini.go
index 91733844e0699b6f1ea62d47e0c4f61b2cde6e36..a846d8d582524bb6bf9c8ed31e3796ec8d94b419 100644
--- a/internal/llm/provider/gemini.go
+++ b/internal/llm/provider/gemini.go
@@ -70,9 +70,8 @@ func (g *geminiClient) convertMessages(messages []message.Message) []*genai.Cont
 			var parts []*genai.Part
 			parts = append(parts, &genai.Part{Text: msg.Content().String()})
 			for _, binaryContent := range msg.BinaryContent() {
-				imageFormat := strings.Split(binaryContent.MIMEType, "/")
 				parts = append(parts, &genai.Part{InlineData: &genai.Blob{
-					MIMEType: imageFormat[1],
+					MIMEType: binaryContent.MIMEType,
 					Data:     binaryContent.Data,
 				}})
 			}