The aim of this study is simulation and forecasting of maximum temperature and heat waves in Urmia city from 2020 to 2050 in order to predict and reduce the negative effects of a sudden increase in temperature, which is simulated using SDSM software and CanESM2 model And is predicted using the most appropriate RCP scenario for the next 31 years. For this purpose, the maximum daily temperature data of Urmia from 1961 to 2005 were obtained from the Meteorological Organization and forecasted. The innovation of this study is using the least error RCP scenario for more accurate prediction. According to the results, RCP 8.5 scenario was selected as the least error scenario for forecasting. According to the results the average maximum temperature in Urmia will decrease from late winter to late spring compared to the base period and in mid-summer there will be a slight increase. In general, during the years 2050-2020, the maximum temperature trend of Urmia will be increasing. According to the results of the Baldi index, The heat waves will be short and maximum four days. One-day heat waves will have the highest frequency and will have a slight upward trend, Two, three and four day heat waves will have a decreasing trend. In general, short-term heat waves are more likely to occur than long-term heat waves. Also, since the detected heat waves often showed the highest frequency in autumn and winter, so the probability of this hazard occurring in cold seasons is higher than warm seasons.