In this research, perovskite-spinel nanocomposite with formula (x)(Cuo.3Mn0.7Fe2O4)- (1-x)(La0.9o Bi0.10 FeO3); 0 ≤ x ≤ 1, were prepared by the auto-combustion method. A single phase of orthorhombic and cubic structure for La0.9oBi0.10FeO3(LBFO); Cuo.3Mn0.7Fe2O4(CMFO) respectively have been proved for two parents and nanocomposites without any further secondary phase using XRD analysis. High-resolution transmission electron microscopy (HRTEM) images reveal nearly spherical nanoparticles for the parents and agglomerated for nanocomposites. Magnetic hysteresis loops demonstrate ferromagnetic (FM) behavior for the spinel compound and nanocomposite, where LBFO possesses G-type antiferromagnetic (AFM). Competition between FM and AFM phases lead to enhancement in magnetic parameters such as saturation magnetization (Ms), remnant magnetization (Mr) and coercivity (Hc). The magnetic properties at low temperatures show the decrease in magnetization and coercivity with increasing the temperature while the magnetic exchange bias HEB was increased until T=200 K and then decreased. The existence of intergranular magnetostatic interactions between the LBFO and CMFO interact at the interface of nanocomposites and play a decisive role in strain energy, exchange energy, and magnetic anisotropy