Abstract: Sandwich insulation wall panel (SIWP) is a type of precast components with load-bearing, enclosure and insulation functions. The SIWP is composed of inner and the outer reinforced concrete slabs and middle insulation layer. The connectors penetrate the insulation layer and transfer loads from the outer layer to the inner layer. The performance of the connectors is crucial to maintain the safety of the panels. However, the conventional connectors may not have adequate stiffness if the insulation layer is too thick, and the quality control is difficult for the installation. In this study, a GFRP I-shaped connector was developed, the associated anchorage method featured with the anchorage rebar penetrating the holes at connector ends was proposed, and tests and finite element analyses were carried out. The experimental results find that the failure modes of the connector are concrete punching and splitting failure. The pull-out and compression strength of the connector are 25.6 kN and 36.8 kN, respectively. The finite element analyses suggest that the anchorage rebar is important for the failure mode. Based on the test and analysis results, methods to determine the punching failure surface and estimate the load bearing capacity are proposed, which are expected to provide references for engineering design practices.