The present study is a quantitative research which aims to identify the effects of instructional activities based on Multiple Intelligences Theory (MIT) on academic achievement of the Omani students with dyscalculia (OSD). The sample consisted of 14 male and female students in third and fourth grades enrolled in the resource room at Al-Ahed Primary School, Sultanate of Oman. The sample was randomly distributed to control and experimental groups each group included 7 students. The mathematics test (MT) was applied to both groups as pretest and posttest. The students in the experimental group were enrolled in instructional activities based on MIT at resource room for ten weeks, while the students in the control group were received their individual instruction at resource room at the same period. The results indicated that there were statistically significant differences between the performance of the two groups on post-MT in favour of the OSD in the experimental group.