Solar energy is a green and attractive renewable energy source that can be converted for power generation. The objective of this work is to evaluate the potential of dish Stirling systems if they are used in the fourth worldwide largest island of Madagascar. For that purpose, a theoretical model of the dish Stirling system based on the geometrical configuration and heat transfer was developed and coded on Matlab. Simulations were run to investigate the energy efficiency variation of the system for eight main sites in Madagascar. As results, the proposed model enables to represent the system thermal behaviour to assess its efficiency. Among the eight studied sites, those which are on the coastal zones are more propitious to the dish Stirling system. While, in the north and northwest, the sites of Diego Suarez and Majunga present high efficiencies with, respectively, 31.65(%) and 31.07(%), it is in the south in fort-dauphin that thermal efficiency rate is maximal with 32.17(%). Convincing results that suggest that the implementation of this kind of facility will solve a large part of energy supply problems in these regions.