In general, the optical and structural properties of perovskites can be improved by doping in order to use them for various applications. In this work, we have developed by the method of spin coating in one step thin layers of FA1-xMAxPbBr3, x gradually taking the values0.2 0.4 0.6 0.8 and 0.1. An analysis of the structural and optical properties was made after their characterization. The results obtained indicate thatthe thin films produced exhibit low dislocation densities and good lattice strain values. All have a main peak of maximum intensity located at the 2Ɵ angle of 26.84° for the crystallographic plane (111) and their grain size decreases with the increase in the percentage of methylammonium (MA) from 501 nm to 452 nm. From the morphological point of view, we have well-covered, dense and crack-free surfaces. We also obtained an improvement in the band gap which gradually decreases during doping from 2.68eV for 2% MA to 2.40 eV for 10% MA. At the end of our study, it should be noted that MA-doped FAPbBr3 thin films are of goodquality and can be used in the photovoltaic field.