In recent years, Iran in Southwest Asia it has been affected by drought. The purpose of the present study is to analyze and forecast drought in Iran. For this research at first, the precipitation and temperature climatic parameters over a 29 year period (1990- 2018) at 30 stations in Iran Collected. For modeling, the M.S.S fuzzy index, at first uses three indices (SET, SPI, MCZI) using fuzzy logic in Matlab software. Then the indicators are compared and compared with Topsis multivariate decision making model, For Prioritization Drought affected areas were used and finally to forecast the RBF artificial neural network model was used. The Research findings showed that the new M.S.S Index drought class fuzzy index reflected the above three indices with high accuracy and the accuracy of the M.S.S model was confirmed with high confidence. In the drought monitoring years, southern and southwestern stations of Iran such as Bandar Abbas and Ahvaz were more prone to drought (24.30 and 18.47%). In the years to forecast, the drought is expected to extend to the central parts of Iran. Including these stations Semnan and Yazd with drought frequency percent (0.86 and 0.91) are based on M.S.S fuzzy index, respectively.