In order to investigate the effect of fiber volume content on tensile characteristic of Ultra-High Performance Concrete (UHPC), 6 groups of “8” shape specimen were designed, and uniaxial tensile test was performed after 28 days standard curing, the complete tensile stress-strain curves were gotten, the effect of fiber volume content on tensile strength, peak strain and toughness of UHPC were analyzed. Test results show that the fiber volume content can be as much as 5% without workability problem, its tensile strength and peak strain are 8.50 MPa and 1 619 με respectively; with the fiber volume content increase the tensile strength, peak strain, compressive strength and toughness increase as well, the uniaxial tensile constitute of UHPC was finally proposed based on the test results. The results of this paper provide a reference for the application of UHPC material.