A business incubator, as a tool for very young firms, can provide them with very important help when starting a business. It can even influence the success of these firms in the market. At the same time, business incubators have also other socioeconomic objectives, e.g. regional development, technological transfer, development of innovations or creating new jobs. In order to be able to reach these objectives, business incubators should be regularly evaluated, possibly compared with other incubators. Another reason for evaluation is that business incubators are often financed by the public sector. The author of this article created her own model for evaluation of business incubators. This model is called EO-TSF Model and it evaluates the impacts of incubators (impact on firms, impact on other fields of regional development) and the performance of incubators (technical facilities of incubators, incubator services, incubator financing). For each area several indicators were designed. Some of these indicators are explained in the article.