Parents of children with autism spectrum disorder (ASD) face unique challenges, which may affect parenting functioning. However, little is known about gender and cultural variations in parenting stress and styles in these families. The aims of this study were to investigate: (1a) the differences in parenting stress and (1b) social style between Italian and Japanese mothers and fathers of children with ASD; (2) the predictive role of culture, sociodemographic, and child’s characteristics on parenting stress; (3) the predictors of the social parenting style, including parenting stress dimensions. The study involved 92 Italians and 89 Japanese parents of school-age children (5–12 years) with ASD who completed the Parenting Stress Index and the Parenting Style Questionnaire. Results revealed that Japanese parents showed higher parenting stress and less engagement in social style than Italians. Across cultures, mothers used more social style than fathers. Being Japanese and having a child with greater ASD severity predicted higher levels of parenting stress. We also found that country, parent’s gender, and stress related to the dysfunctional interaction were significant predictors of parenting social style. Our findings highlight the importance of a cross-cultural approach to better understand the experiences and needs of mothers and fathers of children with ASD.