The purpose of this study was to investigate the effect of using hard and soft scaffolding on Iranian EFL learners' reading comprehension ability in two different experimental conditions, i.e. symmetrical and asymmetrical. One hundred and twenty Iranian intermediate EFL learners were recruited from a population of 400 based on their performance on a placement test. They were randomly assigned into five groups (four experimental groups and one control group), each containing 24 participants. A pre-test of reading comprehension was administered to ascertain the homogeneity of the participants. Then, the experimental groups were exposed to one of the intended treatments for 20 sessions, while the control group received only regular classroom reading instruction. Finally, the learners were given a post-test of reading comprehension used to measure their reading skill. The findings revealed that scaffolding had a positive effect on reading comprehension ability of EFL learners. Soft scaffolding was observed to be effective in asymmetrical condition; however, in symmetrical condition, the effectiveness was not observed. Moreover, hard scaffolding was found to be effective in both symmetrical and asymmetrical conditions. In both of these arrangements, the participants experienced improvement in their performances on the posttest. The implications are discussed in terms of the efficacy of hard and soft scaffolding in symmetrical vs. asymmetrical conditions in enhancing EFL learners' reading comprehension.