Objective: This study investigated psychological mechanisms underlying the relationship between family socioeconomic status (SES) and problem behaviours in Chinese children. Methods: Participants were 1128 children (556 females) from two Chinese elementary schools, aged 8-13years (M =10.82, SD =1.26), attending the 3rd-6th grades. Children provided self-report on parental emotional warmth and psychological suzhi, whereas parents reported on SES and problem behaviours. Results: Data analyses, including structural equation modelling (SEM)-employed to test a three-path mediation effect of parental emotional warmth and psychological suzhi after controlling for gender and grade-revealed that: (1) SES, parental emotional warmth, and psychological suzhi were negatively correlated with children’s problem behaviours; (2) SES indirectly affected children’s psychological suzhi through parental emotional warmth; (3) psychological suzhi mediated the relation between parental emotional warmth and problem behaviours; and (4) children belonging to families with low SES were less likely to receive emotional support from their parents. This significantly predicted low psychological suzhi levels, which in turn negatively affected problem behaviours. Conclusions: Strategies that help parents provide warmth and support and those that help children improve psychological suzhi may help reduce problem behaviours in vulnerable groups.