In recent decades, extreme hydrological events such as drought and flood have been increased in arid and semi-arid regions as a result of climate change. Hence, it is of significance to evaluate their changes in terms of intensity, duration and frequency and the interaction between them. The current study analyzed the characteristics of severity, duration and number of occurrences of drought and flood hazards during the period 1983-2022 using the long-term streamflow data in the basins South Baluchistan, Hamun-e Jaz Murian and Hamun-Mashkel. The results indicated that Southern Baluchistan has experienced larger magnitude, more severe and longer duration of hydrological floods and droughts over the last four decades. Flood magnitude at Bahot, Kehir, Pirsohrab and Kariani stations in this basin increased from 217 m³/s, 225 m³/s, 191 m³/s and 244 m³/s in the first decade to 255 m³/s, 291 m³/s, 291 m³/s and 554 m³/s in the third decade. Similar results were observed for Hamun-e Jaz Murian and Hamun-Mashkel basins. However, the number of flood occurrence in Hamun-e Jaz Murian and Hamun-Mashkel basins has been decreased. The results also showed an increasing trend for drought intensity and the number of occurrence changing from 1.3, 5.7 units in the first decade to 1.6, 4.3 units in the fourth decade, respectively. The duration of drought also increased from 7.5 months in the first decade to 14 months in the last decade.These results refer to the fact that the south-eastern regions of Iran have been affected by the integrated effects of floods and droughts, especially during the last decade. Regarding to the economic and social consequences of the increasing flood and drought risks, the appropriate planning and taking actions by the relevant authorities and institutions would be needed for adaption and reduction of the undesirable effects.