This study aimed at investigating the effect of scaffolding on English as a foreign language(EFL) learners' reading comprehension. It tried to answer if scaffolding improves reading comprehension skill, and if there is any significant difference between the effect of scaffolding and traditional instruction on EFL learners' reading comprehension. Fifty-nine Iranian female intermediate EFL learners participated in this study. They studied at Novin English language institute in shiraz. Oxford Placement Test was used as an instrument of this study. Learners were assigned into two groups: Scaffolded group and traditional group. Learners who were in scaffolded group received scaffolding instruction as a treatment. Learners who were in traditional group received traditional instruction. This study lasted for one term. To this end, Paired t-test and Independent sample t-test were run. Paired t-test showed that scaffolding had a positive effect on EFL learners' reading comprehension. Because, p value was. 000 (p<.05) which indicated there was a statistically significant difference between pre-test and posttest of scaffolded group. Moreover, Independent sample t-test indicated that scaffolding improved EFL learners' reading comprehension greater than traditional instruction as, p value was .036 (p<.05) which showed that there was a statistically significant difference between the two groups. This study showed that scaffolding is suitable and useful for enhancing learners' reading comprehension. So, a lot of stakeholders can benefit from using scaffolding, especially, teachers who want to teach not only reading skill but also other skills such as writing, speaking, and listening, and students who want to boost their language skills.