To explore the mechanical performance of aluminum alloy hub joints in spatial structure system, nonlinear finite element software ABAQUS is used to establish refined numerical models for 25 aluminum alloy hub joints with different sizes to study the tensile and compressive properties. The effects of hub body groove spacing, tooth spacing, tooth width, tooth depth, and other factors on the mechanical performance of the nodes are studied. Results show that the tensile bearing capacity of the joint is mainly borne by the concave and convex grooves between the hub body and the embedded part of the rod. When the parameters are changed, there are four failure modes in the tensile limit state: hub body convex tooth flexural shear failure, hub body innermost groove flexural shear failure, hub body outermost groove flexural shear failure, and hub body convex tooth shear failure. Within the range of study, if the hub body groove spacing and tooth width are increased, the tensile ultimate bearing capacity of the nodes increase by 71.3% and 112.9% respectively. The stress of joints is mainly caused by instability, and the change of parameters have little effect on the pressure of joints. Finally, the formula of ultimate bearing capacity and the design suggestion are given.