In 2012, Micro Small and Medium Enterprises (MSMEs) has absorb about 97,16% labours in Indonesia and 90,12% of labours in Indonesia is working in microbusiness sector. One example of microbusiness type that popular in urban area specially Jakarta is warung tegal (warteg). This study will explain how warteg makes profit and maximize its profit.

MR=MC rule applied for all firm type neither purely competitive, monopolistic, monopolistically competitive, oroligopolistic to analyze how they maximize profit in short run neither maximize profit or minimize loss by producing the output at which marginal revenue equals marginal cost. Further, this study will explain the problem faced by warteg to produce at MR=MC point.