The present invention discloses an experiment simulation device for a fine-bundle type fuel assembly. The device comprises a conductive head, a heating element and a conductive assembly, wherein the conductive head, the heating element and the conductive assembly are sequentially connected from top to bottom. The conductive head is provided with a through hole for being connected with the heating element. The upper surface of the through hole is in the form of an inverted conical surface. Two annular tongue surfaces are arranged below the conductive head and are symmetrically arranged with the through hole as a center of symmetry. According to the technical scheme of the invention, the device can bear high-temperature and high-pressure conditions. By means of the device, the geometric construction and the nuclear heat release characteristics of a prototype fuel assembly can be simulated. Therefore, the experimental research on the flowing condition, the heat transfer condition and the thermohydraulics of the fine-bundle type fuel assembly can be conducted.