This paper reports the results of an epidemiological study of psychological disorders among the rural population of Meibod, in the province of Yazd, with an age range above 15 (N=400). The main instrument was SCL-90-R. A score of 0.4 indicating GSI level and reported in a previous research was chosen as a cut off point. Subjects scoring above this point and an equal random number scoring below that point, were eveluated by two psychiatrists. The results showed that 12.5% of sample suffered from some psychological disorders: affective disorders 5.75% anxiety disorders 5.5%, Somatoform disorders and organic states, each with a rate of 0.50%, and schizophernia with a rate 0.2%. Prevalence was higher for women, individuals with lower education, married, unemployed, house wives, and for those within the age range of 25-44. High reliability and validity was found for the SCL-90-R as an epidemiological instrument.