Since 1958, when the malaria eradication program officially started in Iran, great strides has been made in controlling the disease in most of the country. However, because of certain technical, operational and administrative problems, malaria is still highly prevalent in southeastern Iran, affecting 6% of the population. The situation of malaria in Iran from 1975 through 1990 is discussed in detail, with particular emphasis given to the epidemiological characteristics and vector transmission factors in each region of the country.