Objective: This research is aimed to investigate the effect of rhythmic movement and music on attention span of mentally-retarded girl students.

Materials & Methods: Twenty six mentally- retarded forth and fifth graded girls who were educating in an exceptional children school in shahr-e-rey participated in this survey. In this research which is an experimental – interventional study with a pretest-posttest and control group design, the students were selected by convenient sampling and assigned to two matched groups by balanced randomized method. Then musical activities intervention including music and rhythmic movements executed in experimental group for 15 weeks and twice in a week. During this period the control group received routine educational program. Before and after intervention, the attention spans of two groups were assessed by cancellation subscale of KLT. Data were analyzed by use of non – parametric statistical tests such as: Wilcoxon test and U-Man-Witney test.

Results: There was significant difference in experimental group between mean of attention pretest and posttest scores (P<0/001), but in control group, there was no significant difference (P=0/367). Also, there was significant difference between mean of attention scores of two groups after intervention (P=0/002), but there was no significant difference before intervention (P=0/520).

Conclusion: This finding reveals that musical activities can enhance attention level in mentally-retarded students.