Weather patterns affect vegetation fluctuations. And its effect can be seen in the rapid response of vegetation and its growth changes to the fluctuations of climatic elements. The aim of this research is to analyze the relationship between the vegetation cover of Sistan and Baluchistan province and the pattern of connection with the Indian Ocean Dipolar Oscillation (IOD) in different seasons of the year. For this purpose, the normalized vegetation cover (NDVI) data of Modis sensor has been used during the statistical period from 2001 to 2022. At first, the areas with vegetation of the province (areas with average NDVI higher than 0.12) were separated. Then, according to the severity and weakness of the vegetation index values, it was normalized and to determine the sensitivity of each class with the pattern of connection with the Indian Ocean Bipolar Oscillation index, it was divided into three classes: thin class, medium class and thick class. The results indicate that the dispersion of positive and negative correlation coefficient does not follow a specific pattern. The highest positive correlation coefficient of vegetation cover in all three thin, medium and dense areas is related to the spring season with (r 0.450; p < 0.05) and the lowest correlation is observed in the winter season. Since the positive (rainfall increase) and negative (rainfall decrease) phases of the IOD index have a direct effect on the summer rainfall in the south of the province, it is possible to estimate the amount of vegetation cover with a delay of one to two months in the south of the province using the state of the Indian Ocean bipolar index