One of the important problems in agriculture, especially in developing countries, is the shortage of tractor power in agricultural fields. In this study distribution of available tractor power among provinces of Iran was investigated. Output energy from fields of each province and also potential energy of available tractors was calculated for tree years. These tow factors helped to present a mechanization index (w). This index shows amount of output energy relative to available tractor power for each province. Through all provinces, Kermanshah province had maximum value of this index (27.34) and Hormozgan province had minimum of that (0.39). Provinces were classified according to amount of their need to tractor power using mechanization index (w) and degree. This pattern can be used to distribute power among provinces. Also, in order to raise mechanization index (w) and degree was recommended to use appropriate agronomical pattern so that operations needing to tractors must be optimally spread during year.
