Nowadays, cellular phones are widely used, but most people seem do not aware of the effect of radio frequency electromagnetic radiation (RFEMR) on human body, especially the male reproduction system. The objective of this study is to investigate the biological effects of RFEMR of cellular phone on sperm motility and sperm count. Sixteen mice of BALB/c strain were divided into four groups: mice in the control group were not exposed to RFEMR, mice in the the first group were exposed to 20 times/day intensity, the second group to 40 times/day, and the third group to 80 times/day. Mice were exposed to 1900MHz at specific absorption rate of 96 mW/kg for 7 days. Sperm motility and sperm count were analyzed by means of Oneway ANOVA using SPSS 13.0. There were highly significant differences of sperm motility between the exposed mice groups and the control group (p<0.01), but no significant differences among the three exposed groups (p>0.05). There were also highly significant differences of sperm count between the exposed groups and the control group (p<0.01), and the differences among the three exposed group were significant too (p<0.05). It can be concluded that exposure to cellular phone electromagnetic radiation may reduces mice sperm motility and sperm count.