Optoelectronic devices applications based on Organic-inorganic perovskites are promising and effective low-cost energy materials due to their exceptional physical properties which include high carrier mobility, high optical absorption coefficient, and long carrier diffusion length. In the presented work, a TiO2/NiO+5% Fe quantum dots (QDs)-doped CsMAFAPbI2Br2 perovskite heterojunction broadband photodetector was fabricated on FTO/glass substrate. The photodetector can detect a wide range of wavelengths, from UV to Vis (100-800 nm), has high responsivity (0.99 A/W), and has excellent detectivity (8.9 × 10 12 Jones). Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic force microscopy (AFM), and electrical (I-V) characterization were used to measure the responsivity and detectivity of the photodetectors. Doping with NiO+5% Fe QDs protected the device from oxygen and moisture and improved the morphology of the perovskite by reducing pit defects. The results showed high performance and the potential of a NiO+5% Fe QDs-doped triple cation perovskite photodetector device.