diff --git a/openai.go b/openai.go
index caed728..6f1909d 100644
--- a/openai.go
+++ b/openai.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	oai "github.com/sashabaranov/go-openai"
+	"strings"
 )
 
 type openai struct {
@@ -72,6 +73,20 @@ func (o openai) requestToOpenAIRequest(request Request) oai.ChatCompletionReques
 		res.Temperature = *request.Temperature
 	}
 
+	// is this an o1-* model?
+	isO1 := strings.Split(o.model, "-")[0] == "o1"
+
+	if isO1 {
+		// o1 models do not support system messages, so if any messages are system messages, we need to convert them to
+		// user messages
+
+		for i, msg := range res.Messages {
+			if msg.Role == "system" {
+				res.Messages[i].Role = "user"
+			}
+		}
+	}
+
 	return res
 }