This study investigates the relationship between epistemic beliefs and academic performance among a group of high school students in United Arab Emirates (UAE). Despite some contradictions, the general trend in the literature is that more mature students usually outperform students with naïve epistemic beliefs. We hypothesized that this relationship is reciprocal and learning strategies and task demands play a key role in building the schemas of epistemic beliefs. Accordingly, the requirements of traditional teaching and assessment methods might lead students to adopt less advanced epistemic beliefs that might be consistent with traditional learning strategies and task demands. To test this hypothesis, we compared the epistemic beliefs of high, average, and low level students (n = 165) in the traditional, developing educational system in UAE. Students were classified according to their performance on two formats of assessment; the regular exams and the continuous evaluation, using Arabic, standardized version of Epistemic beliefs Inventory prepared by Schraw et al, (2002). For the two assessment formats, the results were inconsistent with the traditional findings in the literature as advanced and medium students got higher scores (immature beliefs) than low level students on most epistemic beliefs, with the exception of the beliefs in Innate Ability (IA), where weak students got higher epistemic beliefs than advanced or medium level students. The results were discussed as an indication that academically better students were more able to adapt to the system requirement by adopting naïve epistemic beliefs. Also, the results were discussed within the Arab/Emirati cultural context.