To explore the mechanical behavior of a new type of steel hanger joint of secondary beam to primary beam in timber structures, static vertical loading tests of eight specimens using the new hanger joint are carried out based on the ASTM test standards. The load-displacement curves of the joints between the secondary beams and primary beams, as well as two typical failure modes are obtained. By using ABAQUS, three-dimensional solid finite element model of the proposed joint is established. The accuracy of the finite element analysis is verified by comparing with the experimental results. Based on the parametric analysis of the hanger joints, the influence of the thickness and width of the hanger flanges on the shear capacity and stiffness of the joints is studied. Calibrated by the detailed stress analysis and the test results, a simplified mechanical model is proposed, and prediction formulae for the shear capacity and failure modes of the hanger joint are recommended, which are in good agreement with the experimental results.