Cattle’s rearing in Botswana is undertaken in two sectors: the communal and commercial. The communal sector is exclusively free range and therefore depends on biomass production. This makes the systems highly susceptible to drought. One strategy that has been devised by farmers to adapt to drought has been to overstock. However, this strategy may not be the best adaptation strategy as it leads to overgrazing and quick depletion of scarce biomass during the drought years. Climate change may increase the vulnerability of the communal cattle sector in the country mostly through changes and variability of rainfall. In the article, we determine the reliability of the rainfall in the Khurutshe area, Botswana. Vulnerability of the cattle sector to system severe failure is also determined. Lastly, the effects of climate change on return period of drought are investigated. Results indicate that the reliability index of rainfall in the Kgatleng District is 0.5. The vulnerability index of the cattle is estimated at 8000 per year. Lastly, using SimCLIM computer model climate change will shorten the return period of mild drought from 2 years to 1.6 years by 2050. These findings have serious implications on the recovery period of the cattle to withstand the next drought period.