Ultra-high performance concrete (UHPC), as an advanced cement-based composite material, is widely used in special environments such as high cold, high saline, and ocean, or in building structures with large span and special strength requirements because of its excellent mechanical properties. Aiming at the methods for mechanical properties and improvements of UHPC, this paper starts with analyzing and introducing the latest research achievements in the mechanical property and improvements of UHPC in detail from the perspectives of design theory and preparation method, mechanical properties mechanism and characterization, influencing factors and control methods, and subsequently combines, analyzes and summarizes the material mixture design, curing regime, service environment of UHPC. It concludes with looking forward to the preparation method, durability research and related technical specification system of UHPC, which aims to promote the research, application and popularization of UHPC in engineering practice.