Micro-enterprises play a crucial and strategic role in underpinning the national economic structure, particularly regarding labor absorption and driving grassroots economic activity. However, this sector frequently faces perennial internal limitations, notably regarding financial management and inefficient working capital administration. This study aims to analyze in depth how fundamental managerial economics concepts—including demand analysis, cost structure optimization, economic trade-offs, and risk management—can be practically adapted to working capital management within micro-enterprises. Employing a descriptive qualitative method with a case study approach, data were gathered through in-depth interviews, participant observation, and the documentation of simple financial records from several micro-entrepreneurs. The findings indicate that the disciplined application of simplified managerial economics principles can transform business governance; this is evidenced by improved cash turnover efficiency, optimized inventory levels to avoid opportunity costs, and precision in formulating trade credit policies. Although limited financial literacy and owner behavioral biases remain significant obstacles, the implementation of practical analytical tools has proven effective in minimizing liquidity risk while simultaneously boosting business profitability on a sustainable basis.