Abstract: Objective：To investigate the oocyte aneuploid in mice with the method of chromosome C-banding staining. Methods：The standard Giemsa C-banding staining and the modified Giemsa C-banding staining were used to show mouse chromosomes, respectively. The DAPI （4′, 6-diamidino-2-phenylindole） staining, so-called fluorescence C-banding staining, was used to show oocytes. Subsequently, the morphology and number of chromosomes were analyzed with fluorescence microscope. Results：Chromosomes were weakly stained by the standard Giemsa C-banding staining, while chromosomes were easily dissolved by the modified Giemsa C-banding staining. The fluorescence C-banding staining showed superiorities, such as the increased contrast degree between the brilliant white centromeres and the strong blue arms of chromosomes, and the shorten dyeing time. Conclusions：The study suggested that the fluorescence C-banding staining was a simple and rapid method to identify aneuploidy of mouse oocytes.

Key words: Mice, Oocytes, Chromosomes, Aneuploidy