Objective:To explore the characteristics and correlation of psychological defense mechanism and coping style of parents of children with autism spectrum disorder (ASD) .Methods:This study is a cross-sectional study. From March to August 2021, 223 parents of children with ASD in the Child Healthcare Department of Children's Hospital of Chongqing Medical University were selected by convenient sampling. The parents of the children were investigated with the General Information Questionnaire, the Defense Style Questionnaire (DSQ) and the Simplified Coping Style Questionnaire (SCSQ) . Pearson correlation was used to analyze the correlation between psychological defense mechanism and coping style. Multiple linear stepwise regression was used to analyze the impact of defense styles on coping styles. A total of 223 questionnaires were issued, 210 were recovered, and 206 were valid, with an effective recovery rate of 98.10% (206/210) .Results:Among 206 parents of children with ASD, the scores of mature, intermediate and immature defense types were (4.85±1.20) , (4.33±0.90) and (3.98±1.43) respectively. The scores of positive and negative coping in SCSQ were (1.76±0.53) and (1.18±0.58) respectively. Pearson correlation analysis showed that mature defense mechanism was positively correlated with positive coping ( r=0.26, P<0.01) and negatively correlated with negative coping ( r=-0.22, P<0.01) , and the immature and intermediate defense mechanisms were negatively correlated with positive coping ( r=-0.38, -0.22; P<0.01) and positively correlated with negative coping ( r=0.52, 0.43; P<0.01) . The multiple linear stepwise regression analysis showed that the four defense styles of complaint, expectation, sublimation and dissociation were the influencing factors of parents' positive coping in children with ASD ( P<0.05) , and projection, consumption tendency and passive aggression were the influencing factors of parents' negative coping in children with ASD ( P<0.05) . Conclusions:Although parents of children with ASD mainly use positive coping styles, they often use expectation, avoidance, fantasy and other defensive styles in psychological defense. There is a correlation between defense mechanism and coping styles. We should provide targeted social support for parents of children, improve their psychological defense and maintain positive coping styles.