Abstract: Tube-gusset plate connection is an important problem in the design of steel tubular joint of tall towers. Designers could not control limit load because conventional simplified calculation method of joint stress is unable to predict the stress distribution of steel tube when the joint reaches local buckling state. Based on full scale model test, a limit analysis model for determining the ultimate loads of tube-gusset plate connections is established and relevant program is developed. The numerical results, verified by the results of full scale model test and FEM, show that the yield line model has theoretical and practical significance for design.