Duchenne Muscular Dystrophy (DMD) is a devastating neuromuscular disease of childhood which is characterized by progressive muscle weakness that limits the functional activities of daily life in course of time and result in decreased quality of life. The benefits of increasing the physical activity (PA) level and participation on general health status in children with DMD was previously mentioned in literature. Parents have been reported to have an important impact on their child’s beliefs, attitudes, and behaviors in many dimensions of development throughout their lives. Studies showed that there was a significant correlation between parental impact and child’s PA level and participation in healthy children. The aim of this study was to investigate the family impact on PA level, interest in PA, and participation level of their school-age children with Duchenne Muscular Dystrophy (DMD). This cross-sectional, observational study included a total of 30 ambulatory children between 8 and 18 years of age (mean: 8.70 ± 0.84). Physical Activity Questionnaire for Older Children (PAQ-C) and pedometer were used to assess PA level of children while International Physical Activity Questionnaire-Short Form (IPAQ-SF) was used to determine the PA level of parents. Children’s Attraction to Physical Activity (CAPA), Pediatric Outcome Data Collection Instrument (PODCI), and Children’s Physical Activity Correlates (CPAC) questionnaires were also used to evaluate interest in PA, participation level, and family impact on PA level of children, respectively. Low-to-moderate correlations were determined between family impact sub-score of CPAC and PAQ-C, CAPA and PODCI while moderate correlation was found between PAQ-C and parents’ IPAQ-SF score (p < 0.05). This study revealed the importance of parents’ support and encouragement as well as their own PA habit in shaping their child’s behaviors and attitudes towards PA in an early-stage, school-aged DMD population. In order to achieve the goal of increasing PA level and participation of children with DMD, a family-centered rehabilitation approach may be more effective. Clinical Trial Registration Number NCT05209087; Date: 25.01.2022.