With the rapid development of the technologies in electromagnetic and material fields, great progress has been made in the invisibility technology, which has significant application value in the military field. To date, researchers have made extensive and effective efforts in the field of optical invisibility and have proposed some optical invisibility methods based on transformation optics, scattering cancellation, and geometric optics. The presence of metamaterials has turned the optical invisibility technology from theory to reality. Based on the fundamental principles of optics, we introduce the basic principles and current research status of the above several mainstream optical invisibility technologies, analyze the advantages and disadvantages of each technology, and look forward to the future development tendency of the optical invisibility technology.