This paper investigates the behavior of a dovetail joint in simple tension. The failure modes, strength, and stiffness of the dovetail joint are focused on, and a tensile stiffness model and strength evaluation formulas are proposed. The simple tension tests were performed to examine the mechanical behavior of the dovetail joint, and the variation of dovetail angles is the main parameter of the tests. Three governing failure modes in the dovetail joint are considered: bearing failure (Mode II), bearing failure with shear failure (Mode III), and shear failure (Mode IV). The test results show a strong correlation between the stiffness and dovetail angles. The strength is related to the dovetail angles only when the angles are in the range of $10^{circ}{sim}14^{circ}$. The calculation by those two models shows the validity of the proposed stiffness model and strength evaluation formulas.