Abstract: In rebar-anchored socket-type beam-column joints, the connection plate is a critical component governing the overall load transfer performance. However, its anchorage performance remains unclear, and reliable strength prediction methods are lacking. To address this issue, this paper investigates the influence laws of through-rebar diameter and socket-type connection plate opening diameter on the anchorage performance of double-bar socket-type connection plates through pull-out tests, evaluates the applicability of existing shear strength formulas, and proposes a new prediction method for anchorage strength.The results show that the main failure modes of such connection plates are rebar shear failure and rebar bending-shear failure. The rebar diameter is the core factor affecting anchorage performance: when the diameter increases from 8 mm to 16 mm, the anchorage strength increases by 151.5% and the ultimate displacement increases to 8.85 times. Appropriately increasing the opening diameter of the connection plate helps improve both strength and ductility; when the opening diameter increases from 18 mm to 20 mm, the anchorage strength rises by 6.8% and the ductility coefficient increases by 40.6%. Existing formulas exhibit significant prediction deviations and cannot meet the accuracy requirements for engineering design.Based on this, an anchorage strength prediction formula is proposed, which comprehensively considers the shear resistance of through rebars, the shear resistance of concrete dowels in the holes, and the steel plate-concrete interface bond effect. The mean ratio of predicted values to experimental values is 1.03, with a coefficient of variation of 0.09, satisfying engineering accuracy requirements. This study clarifies the influence laws of rebar diameter and opening diameter on the anchorage performance of double-bar socket-type connection plates, and provides a reliable theoretical basis and data support for the anchorage design, parameter optimization and engineering application of such joints.