Objectives: This study evaluated a culturally attuned cognitive-behavior intervention for reducing impulsivity and delinquency-related attitudes and behaviors among Chinese delinquent youth in Hong Kong. Methods: A quasi-experimental design was adopted. Twenty participants received CBI, and 20 received routine counseling for a period of 12 months. All participants filled out a standardized questionnaire before the intervention and at 6 and 12 months of intervention. Results: A series of 2 × 3 analyses of variance were used to examine the Time × Group Effects of the two groups of participants. Results suggested, when compared to the control group, the participants in the experimental group showed greater and continuous positive changes in overall impulsivity, nonplanning impulsivity, cognitive impulsivity, and overall delinquency, with effect sizes showing moderate to large magnitude of change. Conclusion: This culturally attuned CBI program may be a useful inclusion in the outreaching social services for Chinese delinquent youth in Hong Kong.