Parents of children with physical or mental health problems are at higher risk for experiencing parental stress. However, mothers and fathers may experience parental stress differently. The aim was to examine whether mothers and fathers of children with physical and/or mental health problems are equally inclined within the couples to experience different aspects of parental stress when considering child and parent couple characteristics. Single aspects of Parental stress were assessed with nine items from the Parental Stress Scale in 197 parent couples of children aged 1–18 years with physical and/or mental health problems. Agreement within parent couples for each item was tested using two tests of marginal homogeneity for dependent data: a nominal G2-test and an ordinal γ-test. Analyses were conditioned on child gender, child age, couple educational level, and overall parental stress. For seven aspects of parental stress, differences in agreement within the couples were found with at least one of the conditioning variables. For five aspects (item 3, 4, 9, 10, 13) addressing specific personal experience of daily stressors related to having children and feeling inadequate as a parent, the differences were systematic. Mothers were more inclined to experience these aspect of parental stress than fathers, specially mothers of boys, a younger child, in couples with an education above high school or with a higher stress level. Agreement was found for two aspects (item 14 and 16) of parental stress. This study suggests that mothers’ and fathers’ experience of most aspects of parental stress vary within the couples. Knowledge on systematic difference between parents’ experience of parental stress may inform future interventions. For aspects where mothers generally experience the highest degree of stress, fathers may be involved as support. Future studies may explore the role of diagnoses, coping strategies and examine concordance in parental stress symptoms in other subgroups.