Plasma polishing is an advanced surface treatment technology that utilizes ionized gas to enhance material properties by achieving ultra-smooth and contamination-free surfaces. This chapter explores the fundamental principles of plasma polishing, including its mechanisms, process parameters, and material interactions. The advantages of plasma polishing over conventional techniques, such as reduced surface roughness, minimized mechanical stress, and improved precision, are discussed in detail. Additionally, key applications in aerospace, biomedical devices, and semiconductor manufacturing are presented, highlighting its potential in modern industry. Emerging trends and future research directions in plasma polishing are also addressed, emphasizing its role in next-generation digital design and advanced manufacturing.