The invention relates to an ultra-high performance cement-based H-shaped section bar which is formed by pouring an ultra-high performance cement-based composite material. The cement-based H-shaped section bar meet requirements as follows: H/B is equal to 0.8-3; t1/B is equal to 0.03-0.2; t2/H is equal to 0.03-0.2; R1/B is equal to 0.05-0.5; R2/t2 is equal to 0.1-0.5; and R3/R2 is smaller than or equal to 1. According to the ultra-high performance cement-based composite material, the grain composition of a multi-component cementitious material and the grain composition of an aggregate are optimized, and by means of chemical additives, on the premise that concrete has excellent fluidity, the compressive strength reaches more than 170 MPa under the 28 d standard. Through technologies of fibers, reinforcing bars and the like, the cement-based section bar obtains performance of a material component similar to section steel and is applied to structures such as beams, columns, piles and the like of a fabricated building, so that the building has portability and construction speed which are similar to the portability and the construction speed of a steel structure but corrosion resistance and fire resistance which are higher than the corrosion resistance and the fire resistance of a steel-structure section bar.