Abstract： Objective To evaluate the application of domestic probe fluorescence in situ hybridization (FISH) in prenatal diagnosis on uncultured amniocytes aneuploid. Methods One thousand three hundred and sixty-nine uncultured amniocytes (16-24 gestational weeks) from 37 hospitals in China were selected for prenatal diagnosis. 5 chromosomes (21, 13, 18, X and Y) were detected with muhicolor FISH. In the mean time, cytogenetic karyotype analysis was performed as control. Results Of all the samples, 1361 samples were successfully tested by FISH, the rate of successful detection was 99.42% (1361/1369). Thirty-five samples were shown with abnormal karyotypes by domestic FISH probe, the abnormal rate is 2. 57% (35/1361 ), including trisomy 21 (22 samples), trisomy 13 (4 samples), trisomy 18(6 samples), X0 (1 sample) and XXY (2 samples). Results of both FISH and cytogenetic karyotype analysis exhibited extreme concordance. Conclusion Domestic FISH probe used in prenatal diagnosis on uncultured aminiocytes showed the following advantages, such as highly efficient, low cost, small amounts of samples needed and reliable results.