This study investigated the occlusal stress distribution to the implant and soft tissue for the implant-retained overdenture. The stress at the molar residual ridge and the strain around the implant were measured on an experimental resin cast using static and dynamic loading. The influence of connecting structures of stud attachments on stress distribution was discussed. The occlusal stress had a tendency to concentrate on the implant, especially in the areas distal to the implant. The modified magnetic attachment system, using a silicone-covered magnet, provided the optimal stress distribution.