Five hundred intellectually disabled persons of different districts of Haryana state have been recorded and analyzed in the present study. Detailed questionnaire of dysmorphic features has been developed for different level of intellectual disability. More than twenty five dysmorphic features were studied and different level of intellectual disability was determined by Seguin board test. In the present study, 70% intellectually disabled person revealed presence of one or the other dysmorphic features and in 30% of intellectually disabled persons no dysmorphic features could be observed. Presence or absence of unusual features helps in investigation to steer further diagnosis studies. The use of more specific and diagnostic approaches will lead to better clarification of the etiology. An important implication of finding a cause and knowing the aetiology of person with intellectual disability is that their families can be educated about the long term issues such as life span and progression of disease, decision about child bearing and antenatal monitoring of subsequent pregnancies.