The need for low cost photovoltaic solutions is becoming more and more important with the ongoing NewSpace revolution. Within this context, alternative solar cells technologies are under the spotlight, especially perovskites which can potentially reach high specific power (W/kg, W/m3). In this study, we investigate the radiation hardness of multi cation mixed halides perovskites cells of CsxFA1-xPb(IyBr1-y)3 form. The following methodology is applied: 1) Fabrication of batches of perovskite solar cells and ex-situ electrical characterisations. 2) Irradiations with low energy protons, combined with in-situ electrical characterizations. 3) Characterizations of the end-of-life solar cells performances exsitu. The solar cells degradation with fluence will be presented and remaining factors compared with state of the art space solar cells.