Microenterprises are entities that differ from other companies by objectives of the business, the ways of management, the scope of using external financial sources and the level of economic risk. This risk is mainly related to threats directly arising from operational activities. Normally, the small share of loans in financial structure of these entities makes the financial risk relatively low, but increases the operational risk. In case of capital shortage, entrepreneurs cannot expect the involvement of liabilities. Therefore, the assessment of microenterprises requires a slightly different way of measuring efficiency. Widely known methods of measuring the level and the rate of profitability require some modification.