Introduction: According to the World Health Organization, the balanced usage of time contributes to the health and welfare of individuals. Caring for a child with cerebral palsy imposes an extra pressure on parents, especially mothers as the main caregiver. Therefore, this study aims to investigate the relationship between gross motor function ability of children with cerebral palsy and time use of their mothers. Method: Sixty mothers of children with cerebral palsy, sampled conveniently, participated in this cross-sectional study. Children aged between 6 and 11 years with a mean age of 9.04 years old (SD=2.8). The Farsi version of Mothers' Time Use Questionnaire and the Gross Motor Function Classification System (GMFCS) were utilized to collect data. The Spearman correlation coefficient was calculated. Results: The results demonstrated that the allocated time for childcare (rs=0.44) and leisure (rs=-0.37) activities in mothers have significant correlations with gross motor function abilities of their children (P<0.05). Conclusion: Mothers who have children with higher scores according to the GMFCS, had to invest more time to meet needs of childcare activities. Consequently, they were not able to follow their interests and they felt an imbalanced use of time in their life.