Choosing the right material for making injection molding dies is very important, as it affects how well the mold performs, how long it lasts, and how much it costs to maintain. Since the die goes through high pressure and temperature again and again during each molding cycle, it must be made of strong materials that can handle heat, resist wear, and stay dimensionally stable. In this study, I looked into the important factors to consider while selecting the die material, like mold life, how easy it is to machine, resistance to corrosion, and how well it works with different types of plastic. Some commonly used materials like P20 tool steel, H13 tool steel, and beryllium copper alloys are compared based on their properties and usage. I have also included details about special coatings and surface treatments that improve the life and performance of these materials. Overall, with proper material selection based on both technical and cost aspects, manufacturers can improve efficiency, reduce downtime, and increase the lifespan of injection molds.