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Drought is the single most important environmental factor that causes cattle population fluctuations in northern Kenya. The way the grazing lands and animal populations are affected by drought requires long-term monitoring. However, in northern Kenya, patterns of cattle mortality following multiple drought episodes and recovery have not been compared before. This study compared effects of two droughts (1983/1984 and 1991/1992) and three recovery periods (1984, 1992 and 1996) on cattle population in Obbu, northern Kenya. Cattle mortality in terms of age-sex classes; calves, immature animals, breeding females and mature males were compared to understand drought impacts, while relative growth rates of herds and percentage of recovery to pre-drought cattle population levels were determined to understand recovery. The droughts altered herd structure and resulted in greater mortality among calves and breeding females (especially during 1983/1984) than immature animals and mature male cattle. Drought stress in terms of cattle mortality varied from area to another but at the regional level it was less during the 1983/1984 drought (69·8±2·0%) than 1991/1992 (86·8±1·9%). The pre-1983/1984 drought herd size for the Obbu region explained 12·4% of the variation of the post-drought cattle population, while the pre-1991/1992 drought population explained <1% of the variation. Although cattle mortality was weakly linked to the pre-drought population, it was influenced by factors such as disease epidemics and poor nutritional quality in forage. Relative growth rates of herds in Obbu averaged 3·5% year-1after the 1983/1984 drought leading to full recovery in 7 years, while, after the 1991/1992 drought, mean relative growth rate was 2·8% year-1, which after 5 years only achieved ca.32/ recovery of the pre-1991/1992 drought cattle population.