Objective: This study aimed to examine the efficacy of the Parent-Child Interaction Therapy (PCIT) in Hong Kong Chinese families, using randomized controlled trial design. Methods: The participants included 111 Hong Kong Chinese parents with children aged 2--7 years old, who were randomized into the intervention group (n = 54) and control group (n = 57). The participants were requested to complete a set of questionnaires on child behavior problems and parenting before and after intervention. They were also assessed by PCIT therapists using "Dyadic Parent-Child Interaction Coding System: Abbreviated Version" (3rd edition) before and after intervention. Results: The results indicated significant decrease in child behavior problems, parenting stress, negative emotions, negative parenting practices, and increase in positive parenting practices in the intervention group, compared with the control group. Conclusion: The results provided encouraging evidence that the PCIT was effective with Hong Kong Chinese families.