This study investigates the spatiotemporal characteristics of meteorological drought over the past 50 years in Iran's four distinct climates: Hyper-arid, Arid, Semiarid, and Humid. Employing three drought indices (Standardized Precipitation Index, Reconnaissance Drought Index, and Standardized Precipitation Evapotranspiration Index) at multiple timescales (1-, 3-, 6-, 9-, and 12-months), the analysis utilizes data from 41 synoptic meteorological stations spanning the period from 1969 to 2019. Results reveal a temporal increase in the duration and intensity of drought events, particularly post the 1998-99 period. The longest extreme drought, lasting 40 months, occurred during Dec 1998-Mar 2002 and Jan 2018-Mar 2018. Spatial patterns indicate a uniform rise in drought intensity across timescales and indices, transitioning from humid and semiarid to arid and Hyper-arid regions. Average drought durations for SPI, SPEI, and RDI indices are 9, 12, and 9 months, respectively, while mean drought frequencies stand at 14%, 17%, and 13% for SPI, SPEI, and RDI indices. Notably, SPEI exhibits greater duration and frequency of drought events, especially in arid and Hyper-arid regions. The research underscores the pivotal role of climatic variables in delineating drought characteristics and emphasizes the significance of selecting appropriate drought indices across diverse climates.