Climate change is an observable variation in the climate systems that are attributable to human (anthropogenic) activities and natural process (biogeographical), which alters the atmospheric composition of the earth and ultimately leads to global warming. The relationship between climate change (measured by increasing temperature trend and decreasing rainfall trend) and the business activities of cassava farmers in Ogun State, Nigeria appears not to have been fully examined; this study examines the relationship between climate change and the business activities of Cassava farmers in Ogun State. This study employs survey research design, through the administration of structured questionnaire to cassava farmers in Ijebu-Igbo, Ogun State. The research instrument (questionnaire) was validated using content validity index, through the assessment of five academics staff (in the departments of business administration and agriculture) at Olabisi Onabanjo University, Ago-Iwoye and Ibogun Campus, Ogun state, while the reliability of the instrument was tested through test-retest method by conducting a pilot study. The instrument was administered twice within an interval of two weeks and the outcome of the first pilot study was correlated with that of the second and a Cronbach alpha of 0.79 was obtained, which indicated that the instrument is reliable. The regression model was tested using categorical regression with the aid of STATA version 14. The findings revealed that climate change is negatively related to the business activities of cassava farmers in Ogun State with coefficient and probability value of: increasing temperature trend (-0.54, p-value<0.05) and decreasing rainfall trend (-0.72, p-value<0.05). It can therefore be concluded that increasing temperature trend and decreasing rainfall trend, have an inverse relationship with the business activities of cassava farmers in Ogun State, Nigeria. It is recommended that the government should come up with eco-friendly policies as well as liaising with other nations to combat global warming as well as creating irrigational facilities to augment decreasing rainfall, cassava farmers should maximize the use of the raining season as well as creating small irrigational facilities.