Previous studies in parts of Iran report a childhood prevalence of strabismus of 1.2 to 2.3%. The authors aimed to evaluate the prevalence of strabismus in underserved rural areas of Iran in all age groups. In 2015 they conducted a cross section study; 3314 of 3851 subjects participated with 3248 providing data for analysis. Mean age was 37.4±21.4 years; 56.3% were male. Prevalence of heterotropia was 4.3%; increasing from 1.09% in children <5 years of age to 7.45% in adults aged 61-70 years. Heterotropia had no significant association with age, sex or living place. Exotropia was prevalent in 3.87% and esotropia in 0.43%. Exotropia was greater than esotropia in all age groups except children <5 years old where the prevalence of exotropia was 0%. Heterophoria was present in 28.37%: 4.35% in children <5 years and 42.24% in adults aged 61-70 years. Near exophoria was more common than near esophoria and distant exophoria and esophoria. The prevalence of strabismus in young children was similar to other reported studies.