Cytogenetic analysis of granulosa cell tumor of the ovary was performed in two patients. G-banding analysis of cells cultured 3-5 days showed that the karyotype of each tumor contained normal diploid cells as well as cells with identical aberration: trisomy 14. This is the first report of trisomy 14 in two cases of granulosa cell tumor of the ovary. Flow cytometric DNA content analysis was also performed.