Abstract: Conidia are asexual reproduction cells of Penicillium, and their karyotype characteristics have an important influence on the growth, reproduction, genetic breeding of Penicillium. The conditions for achieving the highest proportion of haploconidium were found by using water agar and Czapek-Dox medium over different cultivated days. The karyotype characteristics of conidiospores of Penicillium griseofulvum were observed under fluorescence microscopy by using DAPI staining, with the observations being conducted under water agar and Czapek-Dox medium conditions over different time periods. The results showed that during the growth and development of Penicillium griseofulvum conidia, mononuclear, binucleate, and multinucleate phenomena were concurrently observed, with diverse karyotypes. The proportions of various karyotypes among conidia in different media exhibited significant differences (P＜0.001). However, in the same medium, the proportion of conidia with specific karyotypes at different culture times remained relatively stable, showing no significant difference (P＞0.05). These results provided a theoretical reference for better genetic manipulation of Penicillium griseofulvum.