Based on PIRLS reading competency assessment and questionnaire, the paper investigates the Chinese reading competency of bilingual Chinese students in Singapore. The research selected 7, 9 and 12 years old students as objects. ANOVA-Tukey method was employed to make multiple comparisons of students’ PIRLS reading test results. OLS regression analysis was also performed to explore the impact of various reading strategies on the Chinese reading competency of students of different ages and family language backgrounds. The result shows that for 9-year-old students who use EL and CL equally at home, the development of their reading competency is interfered by both languages, whereas the 12-year-olds do not have this problem. For students mainly using EL, their Chinese reading competency lags behind the other groups after the age of 9. In addition, different types of reading strategies and methods have diverse effects on the reading competency of students with various language backgrounds. Therefore, these strategies should be distinguished in terms of their ways of use and ranges of application.