Injection molding is a widely used manufacturing process for producing plastic components with high precision and efficiency. However, optimizing mold design and machining parameters remains a critical challenge to ensure product quality and minimize defects. This study focuses on the optimization of CNC machining parameters for efficient mold design and validation in injection molding. By using CAD/CAM software for mold fabrication and employing Fusion 360 simulations for plastic flow analysis, this research aims to enhance mold performance and production efficiency. The study explores key factors such as material selection, machining strategies, and injection molding conditions to minimize defects like warpage, sink marks, and short shots. Experimental validation through prototype testing and simulation-driven optimization demonstrates significant improvements in mold accuracy and defect reduction. The findings of this research provide valuable insights into cost-effective and high-precision mold manufacturing, making it particularly relevant for small-scale production using desktop injection molding machines.