The application of multiple materials in vehicle bodies is accelerating as the adoption of lightweight aluminum alloys and composite materials advances rapidly. These materials play a crucial role in reducing overall vehicle weight, enhancing fuel efficiency, and complying with increasingly strict environmental regulations. As the automotive industry continues to evolve toward electrification and sustainability, the integration of lightweight and high-performance materials has become a key design strategy. However, the use of multiple materials creates new challenges in manufacturing, particularly for joining technologies. Since different materials have varying mechanical properties, thermal behavior, and surface characteristics, the selection of appropriate joining methods is essential for ensuring structural integrity and durability. Depending on material types, thicknesses, production processes, and cost constraints, various joining techniques—such as mechanical fastening, welding, and adhesive bonding—are selectively applied. This study focuses on fatigue life prediction for point-based joints commonly used in automotive structures, including flow drilling screws (FDS), blind rivets, and blind nuts. Fatigue fractures in these joints typically propagate in multiple directions: through the sheet thickness and along the in-plane direction. Accurate fatigue life prediction requires numerical simulations that account for both crack propagation paths and the interaction of these paths with joint geometry and loading conditions. Traditional fatigue models often assume a single fracture mode, limiting the ability of these models to evaluate multiple failure mechanisms simultaneously. To address this issue, this study proposes a simplified modeling approach that enables the simultaneous consideration of multiple fracture modes. This paper introduces a numerical analysis-based method capable of predicting the fatigue strength of point joints, and describes the fatigue tests that were conducted to validate the proposed approach. This research contributes to the development of more reliable and efficient design strategies for multi-material automotive structures.