Perovskite solar cells (PSCs) have received attention due to their high-power conversion efficiency close to silicon solar cells (25.7 vs 26.1%), low cost of preparation, and versatile properties. To obtain a highly efficient PCS, the perovskite layer needs to be thermally annealed to complete crystallization and minimization of the defects. The drawback of this process is the creation of strain (compressive or tensile) in the perovskite structure due to the mismatch between the expansion coefficient of the perovskite and substrate. The strain impacts several properties which are related to performance and stability. Here, we propose to evaluate the strain nature (compressive or tensile) in perovskite solar cells under operando conditions (temperature, light, and bias) by full-field diffraction X-ray microscopy. The operando experiment will be performed in a specially designed heating chip substrate and holder for accurate temperature control, illumination, and bias.