Introduction: This study aimed to explore the role of ethnicity and maternal perceived weight status in the association between maternal child feeding practices and childhood Body Mass Index (BMI) at the age of 11–12 years in a multi-ethnic population. Methods: We collected data on child feeding practices by the validated Child Feeding Questionnaire (CFQ) among 2398 mothers of adolescents (Mage = 11.2, SDage = 0.6). Multivariate linear analyses were used to determine the cross-sectional association between child feeding practices (‘Restriction’, ‘Pressure to eat’, and ‘Monitoring’), maternal perception of child's weight status, SDS-BMI, and ethnicity. Results: ‘Restriction’ (β = 0.16; 95% CI [0.11; 0.20]) and ‘Pressure to eat’ (β = −0.32 [-0.36;-0.28]) were significantly associated with child SDS-BMI. Both associations were strongly influenced by the mother's perception of child's weight status. Besides, non-native Dutch mothers performed significantly higher levels of ‘Restriction’ (M±SD = 12.17 ± 4.41) and ‘Pressure to eat’ (10.75 ± 4.03) compared to native Dutch mothers (11.25 ± 4.15 and 9.99 ± 3.83, respectively). Native Dutch mothers performed higher levels of ‘Monitoring’ (17.15 ± 2.54) compared to non-native Dutch mothers (16.73 ± 3.01). Furthermore, children of non-native Dutch mothers had a 0.15 (0.27; 0.46) higher SDS-BMI. Finally, results showed that the association between ‘Pressure to eat’ and SDS-BMI was stronger in native Dutch mothers (β = −0.20; 95% CI [-0.24; −0.15]) compared to non-native Dutch mothers (β = −0.11; 95% CI [-0.18; −0.04]). Discussion and conclusion: Ethnic differences in childhood BMI seemed to be partially attributable to the maternal perception of her child's weight status. Besides, maternal perception of child's weight appeared to play an important role in the association between maternal child feeding practices and childhood SDS-BMI. Hence, our findings contribute to the growing evidence concerning the bi-directional association between child feeding practices and childhood BMI.