Background: The usage of tablet or media tablet computers have become a viable consumer alternative to traditional notebook (laptop) and desktop computing modes. The light weight of the tablet makes it with the users everywhere and so the users spend many hours using it. Objective: This study was conducted to investigate the effect tablet use on muscle performance of wrist and elbow and the effect of period of tablet usage. Methods: The current study was conducted on 60 subjects. They were assigned randomly into three equal studies groups A, B and C with their mean ages were (23±2.63), (22.8±3.01) and (23.4±2.47) years respectively. Peak torque of right elbow flexors and right wrist extensors were measured for groups using Biodex system 3 isokinetic dynamometer. Results: The study revealed that the median score of the peak torque of right elbow flexors at 120 degrees/sec of "group A", "group B", and "Group C" showed there were significant differences (p=0.0001). Mann-Whitney U test (post hoc tests) revealedthat there was no significant difference of the mean values of the "post" test between (group A versus B) with (p=0.383). While, there was significant difference among (group A versus C), and (group B versus C) with (p=0.001) and (p=0.0001) respectively and this significant increase in favor of group (B) and group (A) than group (C). The study also revealed that the median score of the peak torque of right elbow flexors at 120 degrees/sec of "group A", "group B", and "Group C" showed there were significant differences (p=0. 003). Mann-Whitney U test (post hoc tests) revealedthat there was no significant difference of the mean values of the "post" test between (group A versus B) with (p=0.155). While, there was significant difference among (group A versus C), and (group B versus C) with (p=0.001) and (p=0.037) respectively and this significant increase in favor of group (B) and group (A) than group (C). Conclusion: Our study revealed that the peak torque of wrist extensors and elbow flexors of subjects using tablet more than four hours were less than those using tablet two hours and those not using tablet and this show the effect of misuse of tablet on muscle performance in normal subjects.