The present study was carried out to investigate the comparative effect of antonym in-text glosses and description in-text glosses on a group of Iranian EFL learners' reading comprehension. To fulfill the purpose of this study, 60 female intermediate students between 18 and 19 years old were selected among a total number of 90 through their performance on a piloted PET. These 60 participants were non-randomly divided into two equally populated experimental groups. During the process of this study, in one of the experimental groups the participants were given reading texts with antonym in-text glosses and in the other group, the participants were given reading texts with description in-text glosses. A piloted reading comprehension posttest (derived from another sample of PET) was administered at the end of the treatment to both groups and their mean scores on the test were compared through an independent samples <em>t-test</em>. The result led to the rejection of the null hypothesis, thereby, demonstrating that the learners in the description in-text glosses group benefited significantly more than those in the antonym in-text glosses group in terms of improving their reading comprehension.
