_{: Titanium and its alloys have found extensive applications in aerospace, marine engineering, chemical industry, medical devices, and other fields due to their excellent properties. However, the surface performance of titanium and its alloys exhibits deficiencies under certain extreme or specific environments, such as poor wear resistance, low hardness, and insufficient corrosion resistance, which can lead to material damage during service, compromise reliability, significantly shorten their lifespan, and greatly limit their applications. To enhance the surface properties of titanium and its alloys, surface treatment technologies have emerged as effective methods to further improve their comprehensive performance. This review summarizes the characteristics and current research status of surface coating techniques, surface modification technologies, and composite surface treatment technologies for titanium and its alloys, and provides insights into the future development directions and application potentials of these surface treatment technologies.}