The food security question dominates discussions in global forums today. The growing problem of food insecurity in many nations is attributed to climate variability. This study assessed the extent that floods affect agriculture in Gatumba Zone. This study was guided by Food Availability Decline theory and anchored on case study research design. Both primary and secondary data were utilized in this study. The data collected revealed that farm productivity is affected significantly by floods. This research found that recurring floods are a major problem in Gatumba Zone as reported by a majority of the respondents. They affect the performance of the agriculture sector because they destroy crops and farms and also occasion the displacement of farmers, which interrupts their farming activities. The study recommends increased mobilization of financial resources by the government and other partners to support farmers coping mechanism aimed at addressing climate variability dynamics which affect food security. Key Words, Climate Variability, Food Security, Farm Productivity, Food Availability.