Trypan blue staining is a rapid, non-cytotoxic oocyte viability test. Ovaries were collected from 24 slaughtered cattle and were randomly allotted to two groups. Group І culture grade oocytes were selected using morphological grading, whereas live oocytes from group ІІ were selected by trypan blue staining method. Cumulus expansion rate on in vitro maturation was 85.71 per cent in group І, whereas in group ІІ the value was 84.62 per cent. Maturation rate of bovine oocytes did not differ (P > 0.05) significantly between two groups. The results indicated that trypan blue staining has no adverse effect on bovine oocyte maturation in vitro.