Abstract A number of studies have reported that parents of autistic children face higher levels of stress, but few studies examined the stress associated with the home care of children with pervasive developmental disorders (PDD) other than autistic disorder. The aims of the present study were therefore to (i) evaluate the emotional stress level of parents caring for their children with PDD; and (ii) explore the correlates of their emotional stress. Participants were 147 families (147 mothers and 122 fathers) of 158 children with PDD (42 with autistic disorder, 35 with Asperger's disorder and 81 with PDD not otherwise specified). K6 was used to measure the stress level of the parents. Marital relationships and personality were assessed with the Intimate Bond Measure and the NEO Five-Factor Inventory, respectively. The parents also rated the characteristics of their children with PDD through the Pervasive Developmental Disorder–Autism Society Japan Rating Scale (PARS). The mean K6 score of the mothers was significantly higher than that of the women in the general population in Japan. Stepwise multiple regression indicated that the emotional stress of the mothers was correlated with the personality traits of Neuroticism and Agreeableness, perceived Control by the husband, and the children's PARS score. Clinicians can deliver better service by paying appropriate attention to the emotional distress of mothers of children with not only autistic disorder but also other PDD.