In order to zonation and evaluate potential yield of saffron at agroecosystem level in Khorasan Province, Iran, a study was conducted during 2001 and 2002 years, in four selected locations including Birjand, Qaen, Gonabad and Torbat-Haydarieh, which are the main Saffron producing areas in Iran. Data were collected from 160 saffron farms, aged between 1 and 5 years. The obtained data were analyzed statistically and distribution maps were produced using GIS procedure. Results showed that age of saffron farms was the most important factor influencing yield, contributing exceedingly in all fitted regressions for yield in each location. According to the normal frequency distribution curves, yield was varying, at 95% probability, from 0.16 to 7.76 kg ha-1 between evaluated fields, with an average equal to 3.96 kg ha-1. The highest frequency of first irrigation was from 17 October to 1 November and the first flowers were rising from 2 to 21 November more frequently. The five years aged farms had the longest flowering period and there was a positive linear relation between continuance of flowering and yield. The Longest irrigation interval was for Gonabad (24 days) and the shortest was for Torbat-Haydarieh (12 days). The farms in Torbat-Haydarieh had the highest actual yield, which is an indication of better farm management in comparison with other areas. In average, the most of farms yielded about 4 kg ha-1, however there were many farms with more than 7 kg ha-1 saffron yields.