This study investigated the effects of overfishing on communities living around Lake Victoria in Kalangala District, Uganda. Lake Victoria, Africa's largest freshwater lake, is a vital source of livelihood for millions of people in Uganda, Kenya, and Tanzania. However, rampant overfishing has triggered a complex cascade of ecological, economic, and social consequences that threaten the long-term sustainability of fishing communities. The study employed a descriptive research design with mixed methods data collection involving 150 respondents drawn from fishing communities, fish traders, government officials, and NGO representatives. Structured questionnaires, in-depth interviews, focus group discussions, and direct observation were employed. Findings indicate that overfishing has dramatically reduced fish stocks, particularly Nile Perch and Tilapia, with mean annual catch declining by approximately 65% over the past two decades. This decline has translated into reduced household incomes, increased food insecurity, social conflicts over fishing resources, and heightened vulnerability to poverty. The study recommends urgent fisheries regulatory reform, enforcement of closed fishing seasons, and community-based fisheries management approaches.