Research shows that parenting a child with autism spectrum disorder (ASD) is associated with increased marital conflicts and reduced marital love. Less is known, however, about the potential mechanism underlying these associations. The present study tested a family process model linking child autism to parental marriage. We hypothesized that child autistic symptoms would be associated with increased marital conflicts and reduced marital love among parents of children with ASD, and that these associations would be mediated by parenting stress and coparenting conflicts. A total of 382 parents of children with ASD from Hong Kong, China completed questionnaire measures of child autistic symptoms, parenting stress, coparenting conflicts, marital conflicts, and marital love. Structural equation modeling (SEM) and Bootstrap analyses were conducted to analyze the relations among the variables. SEM showed that child autistic symptoms were related to higher levels of parenting stress and coparenting conflicts, which were, in turn, related to increased marital conflicts and reduced marital love among parents of children with ASD. Bootstrap analyses further demonstrated that child autistic symptoms had significant indirect effects on marital conflicts and marital love via parenting stress and coparenting conflicts. Theoretically, this study revealed the potential pathways through which child autism symptomatology may adversely impact the family processes and compromise the marital relationships of parents of children with ASD. Practically, this study pointed to the utility of helping parents of children with ASD to manage child autistic symptoms, alleviate parenting stress, and reduce coparenting conflicts in improving their marital qualities. LAY SUMMARY: This study showed that child autistic symptoms were related to higher levels of parenting stress and coparenting conflicts, which were, in turn, related to increased marital conflicts and reduced marital love among parents of children with autism spectrum disorder (ASD). These findings pointed to the importance of helping parents of children with ASD to manage child autistic symptoms, alleviate parenting stress, and reduce coparenting conflicts in improving their marital qualities. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. Autism Res 2020, 13: 1516-1526. © 2020 International Society for Autism Research, Wiley Periodicals, Inc.