The present study aimed to investigate whether family functioning (FF) could impact gross motor function, activity, and participation in children with cerebral palsy (CP). Sixty-seven children with spastic diplegic CP who were admitted to the Special Education and Rehabilitation Clinic were included in the study. The guidelines of the American Academy of Neurology were followed for the diagnosis of spastic diplegia. The type of home where the family lives, the family's average income, the child's age, gender, and number of siblings, and the age and educational level of the child's primary caregiver were recorded. The gross motor function capacity of children with CP was assessed with the Gross Motor Function Classification System (GMFCS). The Pediatric Evaluation of Disability Inventory (PEDI) was used to evaluate activity and participation performance. The children living in detached houses had statistically higher PEDI mobility levels than those living in apartments (p < 0.05). PEDI's social function and self-care levels were higher in 12 to 18-year-old children with two siblings (p < 0.05). The age and educational status of the primary caregiver were found to have an important impact on the PEDI scores. According to the results, social function and self-care levels were higher in children whose primary caregivers were 30 to 65 years old and had high levels of education above high school (p < 0.05 The effects of family income and gender on PEDI scores were statistically non-significant (p˃ 0.05). Variables related to family functioning had no statistically significant effect on GMFCS scores (p˃ 0.05). These factors can enable healthcare providers to collaborate with the families to develop more comprehensive intervention plans emphasizing family strengths and supporting their needs.