This experiment was conducted to investigate the effect of the cysteine and glutathione on the motility index and morphology of human spermatozoa at the sperm processing in vitro. After treating the sperm with medium containing cysteine and glutathione, we measured the motility index and morphology at 0.5 h and 24 h. 1. Following the sperm culture for 0.5 h after treating the sperm with the medium containing 0, 1, 5, 10 mM cysteine, curvilinear velocity (VCL) was significantly (p<0.05) higher in control than that in all treatments. And straight-line velocity (VSL) was high at 1 mM and average path velocity (VAP) was low at 5 mM and 10 mM. But the motility (MOT) and morphology (NOM) were not different between control and all treatments. Following the sperm culture for 24 h, the MOT was significantly high in treatment groups (58.9, 74.4 and 62.3%), compared with that in control(28.7%) and the VCL was also high in treatment groups (31.4, 37.9, and 34.0 ${mu}{ extrm}{m}$/s), compared with that in control (21.3 ${mu}{ extrm}{m}$/s). The VSL (18.4, 21.7, and 18.9 ${mu}{ extrm}{m}$/s) was significantly higher than control (10.7 ${mu}{ extrm}{m}$/s) and the VAP (20.3, 24.7, and 21.4 ${mu}{ extrm}{m}$/s) in treatments was also compared with that in control (12.6 ${mu}{ extrm}{m}$/s). The NOM was not difference between control and treatments. 2 Following the sperm culture for 0.5 after treating the sperm with the medium containing 0, 1, 5, 10 mM glutathione, the MOT, VCL, VSL, VAP, and NOM were not different between control and treatments. Following the sperm culture for 24 h, the MOT was higher in treatment groups (82.9, 83.6, 83.4%) than in control (51.1%) and the VCL was higher in treatment groups (50.9, 51.3, and 49.4 ${mu}{ extrm}{m}$/s) than control (34.1 ${mu}{ extrm}{m}$/s). The VSL was also higher in treatment (17.1 ${mu}{ extrm}{m}$/s) and the VAP was also higher in treatment groups (30.1, 32.5, and 29.7 ${mu}{ extrm}{m}$/s) than in control (19.8 ${mu}{ extrm}{m}$/s). The NOM was not different between control and treatments.