Objective: The purpose of this study was to assess DMFT and periodontal (CPITN) indices of down’s syndrome patients .Method ;The study was carried out In Down syndrome patients by referring to MR centers of Hamadan , dental caries was scored according to evaluation criteria of WHO about  DMFT and CPITN .Results :18 famale (48.6% ) and 19 male (51.4%) have been evaluated in our study,62% were 9-12 y/o and 38% 13-17 y/o . CPITN was 1 in 73% and 2in 27% . In 72% of  females CPITN was 1 and in 28% was 2.In 74% of males ,CPITN was 1 in 26% was 2. DMFT was 6.7 and 6.1 In females and males respectively The mean DMFT of the subjects was 6.4 .Conclusion :The study showed that patients with Down syndrome had a high prevalence of caries and gingivitis in Hamedan .So it is nessesary to precise and repeated oral health education, periodic control and dental treatments .Also preparing financial and equipment facilities is required.