The aim of this study was to elucidate the role of vitamin C on glycidamide-induced cytotoxicity, oxidative damage and cell death in Leydig (TM3) cells. Leydig cells were exposed to glycidamide (1, 10, 100 and 1000 mu M) and/or vitamin C (50 mu M) for 24 h. After completion of the exposure time, cell viability, amount of lactate dehydrogenase enzyme, apoptosis-necrosis rates, levels of oxidative stress parameters such as hydroxyl radical, hydrogen peroxide and lipid peroxidation were determined in Leydig cells. The results showed that glycidamide administration decreased Leydig cell viability and increased cytotoxicity significantly at high concentration (1000 mu M). In addition, glycidamide generated oxidative damage by significantly increasing the production of reactive oxygen species and lipid peroxidation. Exposure to glycidamide increased the formation of early apoptosis, apoptosis and necrosis in Leydig cells. Consequently, glycidamide has been shown to cause apoptosis due to lipid peroxidation and formation of reactive oxygen species in Leydig cells, and vitamin C has a therapeutic role against toxicity caused by glycidamide.