Changing weather patterns and their variables are already negatively impacting food security by damaging crops, reducing yields, and increasing the prevalence of pests and diseases. These pests and diseases contend with crops for sunlight, water, and nutrients, further diminishing agricultural yields and creating issues for crops that were previously unexposed to these threats. Climate-related disruptions in food distribution and transportation, both internationally and domestically, have a substantial impact on not just safety and quality but also access to food. Prolonged dry spells followed by heavy and stormy rains cause interruptions in food production and transportation, reducing farmers' ability to get their grains to market and potentially affecting food prices. This study assessed farmers’ perceptions of effects of changing weather patterns on food security and their coping strategies towards effects of weather changing patterns in smallholder households in Bukiro Sub County, Mbarara District. A sample of 100 smallholder farmers were randomly selected from four parishes of Bukiro sub county and studied using questionnaire and observations. Key informants Interviews were also conducted with nine technical workers and three opinion leaders. Software STAT 26 and Ms excel version 2016 were used to do data analysis. The study found out that changing weather patterns through its variables specifically heavy and stormy rains, late of set of rains, and prolonged dry spells had significant effects on food security. The perceived effects of changing weather patterns established were drying up of water sources (83.8%), decreased land for crop growing (82.4%), reduction in crop yields (77.7%), drying of pastures for animals (67.4%), drying of crops (58.1%), and occurrence of crop and livestock pests and diseases at (56.6%). Also, the perceived weather changing variabilities were late onset of rains (60.1%), prolonged dry spells were responded at 17.6%, and heavy and stormy rains 22.3%. From the study finding farmers clearly perceived that changing weather patterns had negative effects smallholders’ agricultural production systems impacting negatively on food security