The agricultural production plays an important role in food security. However, crop yields are influenced by climatic factors, particularly rainfall. The aim of this study was to assess the impact of rainfall variability on peanuts, maize, cotton and cashew nuts in the Bagoué region. Rainfall data, agricultural data and information from 300 households, including 100 in Boundiali, Kouto and Tengrela respectively, were collected. The results show that the annual production and surface area of these crops have gradually increased over the years. However, average annual groundnut and maize yields remain low, while cotton yields are consistently higher. Indeed, average annual groundnut yields remain low per hectare, at 0.0003, 0.0004 and 0.001 t/ha respectively from 1990 to 2000, from 2000 to 2010 and from 2010 to 2020. Maize yields were 0.001 t/ha from 1990 to 2000, 0.002 t/ha from 2000 to 2010 and 0.002 t/ha from 2010 to 2020. Cashew nut yields are 0.4 ± 0.11 t/ha from 1990 to 2000, 0.56 t/ha from 2000 to 2010, and 0.59 ± 0.01 t/ha from 2010 and 2020. In addition, cotton yields are higher, with values of 1.43 ±0.44 t/ha, 1.49 t/ha and 1.95 t/ha respectively from 1990 to 2000, 2000 to 2010 and 2010 to 2020. The study reveals a negative correlation between rainfall and yields for all four crops, which suggests that the yields of cotton and cottonseed are higher.