The purpose of the article is to find the answer to the question of whether the model of the accounting system developed by E. Burzym can be used in the description and analysis of the accounting system of open-end investment funds (FIO). The reasoning on the close relationship of the ongoing functioning of FIO with the state supervision and the resulting impact on the character of the accounting system of FIO with special emphasis on functional perspective has been carried out. In following discourse it is shown that the separation of the accounting system of FIO is not fully autonomous with respect to accounting as such and is primarily caused by legislative issues. Also, a detailed analysis of the applicability of E. Burzym’s model as a tool of description of the accounting system of FIO is presented.