In this paper, we interested to the study of structural, magnetic and magnetocaloric properties of polycrystalline (LaPr)_0.7Sr_0.3Mn_0.95(Fe/Cr)_0.05O₃, and evalute thier properties in the case of doped of a small content of Manganese by Iron or Chromium. The samples were prepared using a standard solid state reaction, X-ray diffreaction was used to confirmed the orthorombic phase, the sacaning electron Microscopy is used to observed the morphology of particules and the chimical proportion, the magnetic mesearments were be performed using SQUID. The  SEM results schow that all samples are homogenious in size and chemical composition, the magnetic results indicate a magnetic transition between 320K and 360K for our samplese and a very low corisive field in the range 20 and 108 Oe. The magnetocaloric effect was evalute by calculation of magnetic entropy change and obtained value is 2.5 J/Kg.K in the case of La_0.6Pr_0.1Sr_0.3MnO₃. and the relative cooling power is calcultae to be 312 J/Kg.