This study aimed at investigating the comparative effect of using self-assessment vs. peer-assessment on young EFL learners’ performance on selective and productive reading tasks. To do so, 56 young learners from among 70 students in four intact classes were selected based on their performance on the A1 Movers Test. Then, the participants were randomly divided into two groups, self-assessment and peer-assessment. The reading section of a second A1 Movers Test was adapted into a reading test containing 20 selective and 20 productive items, and it was used as the pretest and posttest. This adapted test was piloted and its psychometric characteristics were checked. In the self-assessment group, the learners assessed their own performance after each reading task while in the peer-assessment group, the participants checked their friends’ performance in pairs. The data were analyzed through repeated-measures two-way ANOVA and MANOVA. The findings indicated that self-assessment and peer-assessment are effective in improving young EFL learners’ performance on both selective and productive reading tasks. Further, neither assessment method outdid the other in improving students’ performance on either task. These findings have practical implications for EFL teachers and materials developers to use both assessment methods to encourage learners to have better performance on reading tasks.