Climate change poses significant threats to rural livelihoods, particularly for smallholder farmers who rely solely on agriculture for their sustenance and economic stability. The study assessed the effects of climate change on rural livelihoods in Rivers State, Nigeria, focusing on the challenges faced by smallholder farmers, the adaptation strategies employed to mitigate these impacts, and the effectiveness of existing governmental and non-governmental support mechanisms for assisting smallholder farmers in adapting to climate change. Utilizing a mixed-methods approach, the research combines quantitative data from surveys with qualitative insights from interviews and focus group discussions (FGD). Key findings reveal that smallholder farmers in Rivers State were experiencing altered rainfall patterns (Mean = 3.60), increased temperatures, and heightened incidence of extreme weather conditions (Mean = 3.50), among other factors, which adversely affect crop yields and livestock productivity. In response to these challenges, the study further revealed that farmers in the study area have adopted various adaptation strategies, including diversifying crop varieties (Mean = 3.70), implementing sustainable agricultural practices, and utilizing improved irrigation techniques (Mean = 3.50). The study revealed that there was not much support mechanism by government and non-governmental organisations in the study area. Thus, the study recommended, among others, the need for government and non-governmental organisations to develop a functional support mechanism to cushion the effects of climate change on rural livelihoods in the study area.