The critical behaviors of the perovskite La0.5Sr0.5MnO3 nanowires bundles around the ferromagnetic-paraferromagnetic (FM-PM) transition through modified Arrott plot and critical isothermal analysis is investigated. The obtained critical exponents are determined by modified Arrott Noakes equation (H/M)(1/gamma) = (T- T-c)/T-c + (M / M-1)(1/beta) under a low external magnetic field of 0-0.8T, where beta = 0.93 and gamma = 2.25 were obtained at Tc approximate to 328 k. The availability of the parameters is proved by fulfilling the Widom scaling relation delta = 1 + gamma/beta which obeys the single scaling equation of M(H, vertical bar epsilon vertical bar) = epsilon(beta)integral(+/-) (H/vertical bar epsilon vertical bar(beta+gamma)). The critical exponents determined in this system is unique and not following theories in any published literature. It may be attributed to the nano-size effect and surface magnetism of this system.