Abstract: Background: Timely analyzing rainfall variability is an important in the economic and environmental conservation mainly in Arid and Semi-arid zones, like Sudan. In arid environments people exclusively depend on seasonal rainfall in their livelihoods. So, whenever life depends on the seasonal rainfall effectiveness, the authorized meteorological information should be guided the policy of seasonal activities. Objective: The aim of this paper is to detect the rainfall variability across the Sudan through analyzing long-term rainfall records. Methods: the annual Spatio-temporal data of long term (1970-2018) of the Sudan Meteorological Agency in Khartoum was used.