The dentistry course in Sri Lanka is conducted in English, a second language for its students. A decade ago, English language proficiency was the key factor in predicting the academic performance of first year dental undergraduates. Since then, changes have been introduced to the teaching programme and examination format to minimise the effect of language proficiency on their performance. This study aimed at re-evaluating the factors influencing academic performance in a similar academic cohort. A total of 306 first year students in five consecutive academic years ranging in age from 20 to 24 years (77% of the total number registered, 36.3% men) were recruited, and a questionnaire was used to collect data regarding demographics, previous academic ability and perceived levels of difficulty of the first year course, English language and its sub-skills. Performances of the English language test and cumulative GPA of the first year course were used as objective indicators of language competency and academic performance respectively. The data were analysed using SPSS 11.5. Hierarchical Regression Analysis revealed that English language proficiency, gender and previous academic ability were the significant predictors of GPA. Students who received a lower GPA perceived English as considerably more difficult compared to the academic course itself; however, students who obtained a higher GPA perceived the opposite. Students' language competency remains the major predictor of academic performance, although previous academic ability and gender emerge as significant predictors. The perceived difficulty, however, of the dental course and of studying in English may also be predictors of student academic performance.