Abstarct: Introduction: Simultaneous occurrence of different mextabolic factor risks, including Hyperglycemia, dyslipidemia, hypertension and abdominal obesity, are called mextabolic Syndrome. since the rate of diabetes, high blood pressure, overweight and lower levels of physical fitness in mentally retarded people are reported more than their healthy counterparts, it’s expected that mextabolic syndrome prevalence be high among them, as well, while this hypothesis is proved in different studies. So, this study tries to survey the effect of aerobic exercises for eight weeks on mextabolic syndrome factors in mentally retarded girls Gonabad city. Methodology: The participants of this study were 22 educable mentally retarded girls who did not participate in any regular exercise during 2 last years. After obtaining consent from patents and completing the Baekce Physical Activity Questionnaire and Physical Activity Readiness Questionnaire(PAR-Q), blood pressure, anthropometric(Height, weight and waist circumference) and biochemical (HDL ,TG ,FBS) measured to identify the people with mextabolic syndrome. Then people with mextabolic syndrome and healthy ones divided into two practice groups and control groups Four groups: healthy Exercise, healthy controls, mextabolic syndrome mextabolic syndrome is exercise and control (four groups: healthy Exercise, healthy controls, training mextabolic syndrome, mextabolic syndrome control) Two practice groups did aerobic exercises at 65-75% heart rate reserve for eight weeks. After practice, the measurement repeated for all the participants. this study evaluate the normality of data using Kolmogorov-Smirnov test. Determination of the differences intergroup and between the groups the T-test and ANOVA test was usd, respectively. if there is a difference between the Data Gabriel's post hoc test was used. (p<0.5) Results: baxsed on he results, while mextabolic syndrome prevalence was high in this study (45.45% of them were suffering from mextabolic syndrome), all the risk factors decreased during eight weeks of practice, Just weight (P= 0/012) and diastolic blood pressure (P= 0/007) and also rated Z Score mextabolic syndrome (P=0/023 ( were significant in practice mextabolic syndrome group and just the weight factor (P=0/014( and diastolic blood pressure (P= 0/032) had significant reduction in practice healthy group. The results of this study showed that after 8 weeks of aerobic practices, between-group difference of practice mextabolic syndrome group with control mextabolic syndrome group was more than between-group difference of practice healthy group with control healthy group. Maybe the reason is more differences of mextabolic syndrome factors from normal range in the practice mextabolic syndrome group, which is led to more significant between-group differences, under effect of exercise period with its more differences for approaching the normal range. Discussion and conclusion: The results show that the reduction of mextabolic syndrome factors can be expected by planning and regular exercises. So, baxsed on this study, the importance of promotion and maintenance of physical fitness to prevent mextabolic syndrome risk in educable mentally retarded girls is confirmed.