Efficient construction site layout planning is crucial for enhancing productivity and safety. This study addresses the complexities of combinatorial optimization in site layout, which involves strategically placing temporary structures while managing multiple objectives. Existing research has often focused on minimizing travel distances between two facilities, neglecting important factors like costs and safety relationships. This research develops a model with two optimization objectives: minimizing travel distance between facilities to lower transportation and construction costs traveling distance and minimizing risks related to interaction frequency between facilities, as increased interaction raises collision probabilities. A genetic algorithm (GA) is employed as the heuristic optimization method. The study includes a case study to validate the proposed model, demonstrating its effectiveness in providing practical solutions for site layout planning by incorporating cost and safety relationships considerations. Offering a more comprehensive approach, this research aims to enhance decision-making and improve overall project execution on construction site layouts.