The critical behavior and magnetocaloric effects of the monoclinic Cr5Te8 single crystal have been studied by using magnetization measurements. Experimental results show that the paramagnetic (PM) to ferromagnetic (FM) phase transition is a second-order phase transition at Tc= 222 K. The detailed critical behavior analysis indicates that the values of critical exponents β, γ, and δ determined by the modified Arrott plots, the Kouvel-Fisher method as well as the critical isotherm analysis agree well with each other and fulfill the Widom scaling law. The critical exponents are close to those expected for the three-dimensional Ising model and the ferromagnetic interaction is at the boundary between long-range type and short-range one. In addition, the magnetocaloric property of monoclinic Cr5Te8 is consistent with the analysis of critical behavior.