The determinants of academic performance have always been the concern of educators. This study examined the effect of deliberate practice and previous knowledge on the academic success of a sample of 181 first-year business students in an elementary accounting course at a self-financed college in Hong Kong. The study had three objectives: (1) to ascertain the role of deliberate practice in their academic success; (2) to determine whether the role of deliberate practice would remain the same if the students' previous knowledge was considered; and (3) to compare the contribution of different measures of previous knowledge to the students' performance in the course. The authors developed hypotheses and a research model and conducted multiple linear regression analyses to measure the relationships between deliberate practice, previous knowledge, and academic success in the course. The authors also developed suggestions for future research.