Abstract: Considering the two main factors of basalt fiber volume fraction and aspect ratio, the axial tensile failure mode, full stress-strain curve, tensile load deformation performance and toughness of basalt fiber concrete reinforced were studied through direct tensile test. The results show that the uniaxial tensile failure of basalt fiber reinforced concrete shows obvious plastic characteristics, and basalt fiber significantly enhances the toughness of concrete under axial tensile load. Compared with ordinary concrete, with the increase of basalt fiber reinforcement factor, the characteristic points and fracture energy of the full axial tensile stress-strain curve increase first and then decrease. Based on the full axial tensile stress-strain curve analysis, the axial tensile stress-strain constitutive model of basalt fiber reinforced concrete about fiber volume fraction and length diameter ratio was proposed, which can be used as a reference for nonlinear analysis and engineering design of basalt fiber reinforced concrete structures and components. The tensile compression ratio, flexural compression ratio and uniaxial tensile failure fracture energy were compared and analyzed. It is found that fracture energy can accurately evaluate the tensile toughness of basalt fiber reinforced concrete (BFRC), and the maximum increase rate of BFRC toughness compared with normal concrete (NC) is 43.0%.