The aim of this study was to investigate the effects of computer games with different stimulating on arousal levels in 8 to 12 years old boys using SCL index and SAM test and the method of the study is quasi-experimental design. The population consisted of all boys 8 to 12 years old at region 4 Education in Tabriz (2011-2012). The sample included 15 boys whom were selected through random sampling method. The arousal levels of participants measured via Skin Conductance Level (SCL), as a physiologic index, in 6 steps including: first baseline, first intervention (Playing the computer game with low stimulating), second baseline, third baseline, second intervention (Playing the computer game with high stimulating) and fourth baseline. In order to analyze the data, repeated measure ANOVA was used.The results showed that the levels of SCL in participants remarkably increased during the interventions phases compared with baselines phases. According to the findings of the study, computer game with high stimulating rate is more effective in raising arousal level in participants than low stimulating game.