diff --git a/src/calibre/utils/img.py b/src/calibre/utils/img.py
index bcb7d333d6..a643b037ec 100644
--- a/src/calibre/utils/img.py
+++ b/src/calibre/utils/img.py
@@ -694,7 +694,7 @@ def convert_PIL_image_to_pixmap(im, device_pixel_ratio=1.0):
     if im.mode == "RGBA":
         fmt = QImage.Format.Format_RGBA8888
         data = im.tobytes("raw", "RGBA")
-    elif im.mode == "RGB":
+    elif im.mode in ("RGB", "CMYK"):
         fmt = QImage.Format.Format_RGBX8888
         data = im.convert("RGBA").tobytes("raw", "RGBA")
     elif im.mode == "1":