OBJECTIVE To observe the pathological changes in ovary or testis of the SD rats after n-hexane inhalation, and to investigate the effects of n-hexane to sexual glands. METHODS Forty-eight adult healthy rats were selected and randomizedly divided into four groups control group and three n-hexane groups (1, 3 and 7 d) six rats for each group. After inhalation, SD rats were killed and n-hexane concentration of blood from celiac artery were detected. Super-oxide dismutase (SOD) glutathione peroxidase (GSH-Px) malondialdehyde (MDA) glutathione (GSH) were measured by photometry, and organ coefficients were calculated. The ovary or testis were embedded with paraffin, sliced, stained by HE method and observed using microscope. RESULTS As the time of n-Hexane effect increased, the activities of SOD, GSH-Px and GSH were decreased, but the content of MDA was increased, especially in the 7 d group (P < 0.01). CONCLUSIONS n-hexane can induce a series of damages in ovary or testis of SD rats, and lipid-pre-oxidation may be one of the effect process.