Abstract: Based on the viewpoint of limit analysis, two equations can be used to evaluate the plastic limit pressures of welded branch pipe tee connection are proposed. The effective factors and the validity of these e-quations are discussed by using the experimental data. The results have shown that the equations derived from the yield of cylinder-cylinder intersection and equal area reinforcement are usable in the engineering design, and more accurate results can be obtained with the equation derived from insersection yield. It has a great value to spread this equation. The plastic limit load of tee connection will increase as the ratio of pipe radius and wall increase. However, the influential law of the parameter d/D and limit pressure need to be studied deeply.