Though numerous studies demonstrated the positive effect of rehabilitation on cerebral palsy (CP) children, there was no literature addressing the role of rehabilitation on mortality among children with CP. Therefore, we aimed to evaluate the impact of rehabilitation intensity on mortality among children with moderate to severe CP. This retrospective cohort study was conducted by National Health Insurance Research Database in Taiwan. Children (< / 12 years) with newly diagnosed moderate to severe CP between 1 January 2000 and 31 December 2013 were included. All patients were followed up for 3 years after CP diagnosis or death or until 31 December 2013. The intensity of rehabilitation therapy within 6 months after CP diagnosis was categorized into < / 6 times and ≥6 times. The Cox proportional hazard analysis was used to determine the association between rehabilitation intensity and all-cause mortality after adjusting age, sex, other demographic factors and comorbidities. Among 3936 severe CP children, 164 (4.2%) died during the 3-year follow-up period. The mortality rate was higher among patients receiving rehabilitation < / 6 times within 6 months than those ≥6 times within 6 months after adjusting demographic profile and comorbidities (adjust HR (aHR): 1.96, 95% CI 1.33–2.89, p < / 0.001). We found that patients who were younger (aHR: 0.84, 95% CI 0.76–0.92, p < / 0.001), who were receiving inpatient care more than twice in 1 year before their CP diagnosis (aHR: 2.88 / 95% CI: 1.96–4.23 / p < / 0.001), and who have pneumonia (aHR: 1.41, 95% CI 1.00–1.96, p = 0.047), epilepsy (aHR: 1.41, 95% CI: 1.02–1.95, p = 0.039) and dysphagia (aHR: 1.55, 95% CI: 1.06–2.26, p = 0.024) have higher risk of mortality. Rehabilitation ≥ 6 times within 6 months has a potentially positive impact on pediatric CP survival. Besides having a younger age, being hospitalized more than twice within a year before diagnosis and having pneumonia, epilepsy and dysphagia were modifiable risk factors in clinical practice for these children.