Studies on the long-term prevalence of parental posttraumatic stress symptoms (PTSS) following child accidental injury are scarce, and findings on risk factors vary. In this follow-up study (T2, n = 69) we determined the prevalence of parental PTSS 2–4 years after accidental injury of their child, compared with 3 months after the accident (T1, n = 135). Additionally, we examined the association between parental and child factors and PTSS severity. Children were 8–18 years old at the time of the accident. Parent and child PTSS was assessed by self-report. Other data were retrieved from medical records and a telephone interview. Parental PTSS was 9.6% at T1 and 5.8% at T2. Acute parental stress as measured within 2 weeks of the child’s accident was significantly associated with parental PTSS severity (T1 and T2), as was the child’s hospitalization of more than 1 day at T1 and the child’s permanent physical impairment at T2. To prevent adverse long-term psychological consequences we recommend identifying and monitoring parents at risk and offering them timely treatment.