Ethylene glycol monomethyl ether (EGME) is known to alter the reproductive function of exposed animals and their offspring; however, its influence on cumulus-oocyte complexes (COCs) remains unclear. This study assessed the toxicity of EGME on oocytes and COCs by analyzing the number of oocytes in the F0 and F1 generations and evaluating apoptosis in oocytes and COCs after treating the F0 generation with EGME. There was a dose-dependent increase in the apoptosis ratios in the COCs from F1 mice, which were not directly exposed to EGME, with apoptosis ratios of 0.065, 0.102, 0.184, and 0.212 for the 0%, 0.05%, 0.1%, and 0.2% EGME dose groups, respectively. The increased apoptosis of cumulus cells may play a role in the toxicity of EGME toward ovarian function. EGME toxicity seems to affect female offspring in future generation(s), but further studies with a large number of animals are necessary to verify these conclusions.