Literature on children's singing development is largely skewed towards findings based on English-speaking children. The present study aims to fill the gap in research through an investigation of the effects of age, gender and language on the singing competency of Cantonese-speaking children. One hundred and twenty children aged 7 and 9 years participated in the study. Sixty children were Cantonese monolinguals and 60 were English bilinguals. Each child performed individually a criterion song and two independent judges rated the recorded singing performance. Welch's model of Pitch-matching Development (2000) and Rutkowski's Singing Voice Development Measure (1998) were used to evaluate singing competency. Results suggest that melodic singing achievement and the ability to use a singing voice are moderately related singing behaviours. Evidence also suggests that gender and language but not age affects singing competency.