The study examined the relationship between internal controls and organizational profitability of Kampala Capital City Authority (KCCA). The research adopted a mixed-methods approach combining quantitative surveys and qualitative interviews, targeting 156 staff members from finance, procurement, revenue collection, internal audit, and management departments. Data were collected using structured questionnaires and semi-structured interviews, analyzed through Pearson correlation, multiple regression, and thematic analysis. Results revealed significant positive relationships between internal control components and organizational profitability. Control environment demonstrated the strongest correlation with profitability (r = 0.728, p < 0.001), followed by monitoring activities (r = 0.694, p < 0.001), control activities (r = 0.671, p < 0.001), risk assessment (r = 0.648, p < 0.001), and information and communication (r = 0.612, p < 0.001). The multiple regression model indicated that internal control systems collectively explained 68.4% of variance in organizational profitability (R² = 0.684, F = 71.38, p < 0.001). KCCA divisions with robust internal controls demonstrated 34.7% higher revenue collection efficiency, 28.3% lower operational costs, and 41.2% fewer financial irregularities compared to divisions with weak controls. The study concluded that effective internal controls constituted critical determinants of public sector organizational profitability, enhancing revenue generation, expenditure management, and institutional sustainability. Recommendations included strengthening control environments through ethical leadership, implementing integrated financial management systems, enhancing internal audit independence, and conducting regular control effectiveness assessments.