Background: Mental fatigue is a psychobiological state caused by prolonged periods of demanding cognitive activity. Objective: This study aimed to investigate the effect of mental fatigue on three-point shots in skilled basketball players. Methods: This study was semi-experimental. For this purpose, 18 male experienced basketball players were selected by convenience sampling and randomly divided into experimental and control groups (control: n=9, experimental: n=9). Participants in the experimental group experienced mental fatigue using strop software and math tests, but the control group did not perform any specific cognitive tasks during this time. Visual Analog Scale and three-point shots were used as a pretest and posttest. For data analyzing, the SPSS 25 was applied, and the significance level was considered at (p<0/05). Results: The results of the study illustrated that spatial working memory played a predictive role in selected attention (same color and font, and different color and font) and performance accuracy; Moreover, mathematical working memory played a predictive role in selected attention (same color and font, and different color and font). However, it did not have a predictive role in performance accuracy. Conclusion: The result of this study supports the theory that mental fatigue had impact on athletic performance. It is suggested that basketball players and coaches consider mental fatigue in sports performance.