These studies report the influence of Cr and Co-doped at Mn-site in perovskite manganite Pr0.75Na0.2Ag0.05MnO3, which were prepared using the solid-state method. The parent compound, Cr-doped sample, and Co-doped sample are called Pr-1, Pr2, and Pr-3 respectively. The focus of this research work was to elucidate how the Cr and Co affected the Jahn-Teller effect by examining the crystalline phase, surface morphology, and electrical properties. These behaviors of perovskite manganite were analyzed by the powder X-ray diffraction (XRD), Scanning electron microscope (SEM) equipped with Energy-dispersive X-ray spectroscopy (EDX), and four-point probe. All samples showed an orthorhombic structure with the Pnma space group according to the X-ray diffraction pattern. Scanning Electron Microscope (SEM) images show that the samples were not regular particles. The grain size decreases from 7.239 μm, 5.957 μm, and 5.576 μm with the replacement of a smaller ionic radius of Cr and Co-doped respectively accompanied by the values of resistivity. The existence of the element substitution of samples illustrated the spectrum of EDX. Apart from that, the value of resistivity shows a continuous decrease from 113.1 Ω, 108.3 Ω, and 106.7 Ω respectively, with the magnetic ion concentration suggestively due to the iso-electronic of Cr-doped ions and Co-doped ions, which improved the conductivity of the samples. Hence, Cr and Co-doped play a crucial role in influencing the physical properties that alter the lattice arrangement and reduce the unit cell volume of all samples for the enhancement of magnetic sensor devices.