Abstract： Objective:Exploring the mediating effect of perceived social support between the maternal personality traits and pregnancy-related anxiety.Methods:Singleton pregnant women who underwent antenatal checkups in the obstetrics department of general hospital affiliated to Ningxia Medical University from July to December 2021 were enrolled in this study to investigate perceived social support, pregnancy-related anxiety and conscious personality traits. Pearson correlation analysis was used to analyze the association between the maternal personality traits, perceived social support, and pregnancy-related anxiety, and the mediating effect of perceived social support was analyzed using Bootstrap method.Results:A total of 1 259 subjects were included in the study, of which 170 (13.50%) pregnant women felt introverted. The total score of perceived social support was (46.37±8.38), and 31.45% of pregnant women had high perceived social support. The total score of pregnancy-related anxiety was (21.48±5.53). The score of worry about fetal health was (10.09±3.24), and 368 (29.23%) of pregnant women had pregnancy-related anxiety. Maternal personality traits and pregnancy-related anxiety were negatively correlated ( r=-0.076, P<0.05) and positively correlated with perceived social support during pregnancy ( r= 0.127, P<0.05). Perceived social support during pregnancy and pregnancy-related anxiety were negatively correlated ( r=-0.236, P<0.05). Perceived social support partially mediated the relationship between the maternal personality traits and pregnancy-related anxiety, with a relative effect value of 37.50%. Conclusion:The maternal personality traits, level of perceived social support and pregnancy-related anxiety are all related. Perceived social support could mediate the relationship between the maternal personality traits and pregnancy-related anxiety.