The study of critical magnetic properties of La0.9Bi0.1MnO3 is reported and discussed. The sample exhibits rhombohedral perovskite crystal structure with trivial lattice structural distortions, surprisingly maintaining the proper stoichiometry and composition as evidenced by energy-dispersive X-ray spectroscopy. The critical behavior observed in the magnetization measurements is studied using different models with proper data analysis attributed to the magnetic frustrations arising due to the inhomogeneities. The zero-field-cooled magnetization measurements below T < TK exhibit frozen ferromagnetic inhomogeneous spin agglomerates. The observed low-temperature-dependent field-cooled magnetization measurement has been approximated by considering the quadratic and non-quadratic dispersion law incorporating corrections to the Bloch’s relation. The exponents like γ and β obtained from critical scaling analysis further confirms the inhomogeneities in magnetic behavior and doesn’t correspond to any of the well-known universality class such as 3D Ising, 3D Heisenberg and mean-field models.