Objective: To investigate the relationship between fine motor skills and executive function in school aged boys with attention deficit hyperactivity disorder (ADHD) aged 6-10 years, so as to provide a reference for promoting executive function. Methods: From November 2022 to May 2021,65 boys with ADHD were recruited from a tertiary hospital in Beijing and a public elementary school in Beijing, and 65 boys with typical development according to age and sex were recruited as controls. Children s fine motor skills were assessed using the movement assessment battery for children, second version (MABC-2), and children s inhibitory control, working memory, and cognitive flexibility were assessed using the Stroop color word test (SCWT), Rey osterrich complex figure test (ROCFT) and trail making test (TMT), respectively. Independent samples t-tests were used to analyze the differences between the two groups, and Pearson correlation analysis and stratified regression analysis were used to explore the relationship between fine motor skills and executive functioning in boys with ADHD. Results: In the fine motor skills test, boys with ADHD scored significantly lower (8.68±3.62) than control boys (11.22±2.27)( t =4.80, P <0.05); in the executive function test, the results of SCWT, ROCFT, and TMT tests were significantly worse in boys with ADHD than in normal boys ( t =-4.53-4.42, P < 0.05). Correlation analysis showed that the fine motor skill scores of boys with ADHD were negatively correlated with the number of word sense errors ( r =-0.35) and color errors ( r =-0.42), and positively correlated with memory scores for delayed structure ( r =0.30) and detail ( r =0.25), which were negatively correlated with TMT-A ( r =-0.34),TMT-B reaction time ( r =-0.26), number of errors ( r =-0.43) ( P <0.05). Stratified regression analysis showed that fine motor skill scores of boys with ADHD were predictive of test results for inhibitory control, working memory and cognitive flexibility, with explanatory rates of 15%, 7%, and 19%, respectively. Conclusion Fine motor skills in boys with ADHD are correlated with executive functions, and fine motor skills could predict inhibitory control, working memory and cognitive flexibility to some extent. The development of fine motor skills in boy with ADHD could promote their executive functions.