Objective: The purpose of this research was to investigate the effect of sensory- motor integration exercises on static and dynamic balance in children with trainable mental retardation.

Materials & Methods: In this semi experimental research, with Purposive sampling method 40 subjects from GOLHAYE BEHESHT rehabilitation and training center with the mean age 8.48±2.81 years and mean IQ 30.62±6.81 participated. All children were pre tested. Then According to both factors (IQ and pretest scores) subjects divided randomly in two (experimental & control) equal groups. Each group were consist of 10 boys & 10 girls .Balance evaluated by balance part of Bruininks – Ossietzky Test of Motor Proficiency were used .experimental group encounter to Sensory stimulation and perform physical exercises during 50 sessions ؛ each session was 45 minutes and 6 times a week . Control group were using the class education programs. After 50 sessions both groups (experimental & control) were post tested

Results: Data analyzed by Uman vitny and observed a significant difference in posttest among experimental and control groups (P<0.05).

Conclusion: Experimental group gained more scores. This research indicated that sensory integration training improve balance (both static & dynamic balance).