Basing on the traditional tri-axial test on large-scale samples, the strength characteristics of municipal solid waste have been studied. The municipal solid waste is divided into three parts: incompressible solid waste material, reinforced material that is difficult to be biodegraded and the material that is easy to be biodegraded. The proportions of these three parts are 35%, 15% and 50%, respectively. Laboratory test has been performed for different initial void ratios, different proportion of ingredients and different confining pressures. The testing results show that the initial void ratio is the main factor that influences the strength of the municipal solid waste. Besides, the principle effective stress increases with the axial strain in a hardening increasing trend, even though the total axial strain has reached 40%. The principle effective stress also increases with the confining pressure that applied on the testing sample. Furthermore, the principle effective stress decreases with the increasing of the initial void ratio.