Objective: To verify the development of fatigue and sex-influence on the handgrip during dynamic contractions in typical children. Methods: Cross-section study. Fifty-eight children, distributed into two groups according to sex (30 boys), aged 8 to 12 years, of both sexes, performed successive dynamic contractions with a bulb dynamometer until they reached maximum perceived effort. The values from the first, the last contractions of the fatigue test, and the measure after 30-s of the last contraction (recovery contraction) were recorded and compared using the linear regression model with mixed effects. T-Student test was used to compare the perceived effort scores and time-to-fatigue between groups. Results: The handgrip values significantly decreased, and perceived effort scores significantly increased in the final measure in relation to the initial measure of the fatigue test. After the fatigue handgrip test, 30-sec of recovery was insufficient to restore the baseline handgrip values. There were no differences between the female and male groups for all variables. Conclusion: The handgrip fatigue test using dynamic contractions showed it efficiently induces motor and perceived fatigue in children, without differences between sexes.