This research focuses on designing and creating a prototype safety device for horizontal milling machines using the Design Thinking method. The study addresses the significant safety concerns in manufacturing environments, particularly the risks associated with operating milling machines, including exposure to metal fragments and direct contact with cutting tools. Through a structured approach following the five stages of Design Thinking (Empathize, Define, Ideate, Prototype, and Test), the researchers developed a flexible safety device tailored to the specific needs of milling machine operators. The prototype was designed to protect operators from metal debris and direct contact with cutting tools while maintaining visibility and productivity. The effectiveness of the prototype was evaluated using the System Usability Scale (SUS) method, with surveys conducted among 30 respondents comprising laboratory assistants and students with experience operating horizontal milling machines. The results showed an average SUS score of 69.25, categorizing the safety device as "Good" according to SUS standards, with 66.7% of respondents rating it positively. The successful implementation of this safety device demonstrates the value of user-centered design approaches in addressing workplace safety challenges. Recommendations include further design refinements, standardization for similar machine tools, training programs, material research for improved comfort, and broader implementation across educational laboratories and small industries.