In order to study dynamic constitutive relatioin of basalt fiber reinforced concrete(BFRC), the impact compression tests on BFRC were carried out with the 100mm-diameter split hopkinson pressure bar(SHPB) device. Obtained the dynamic stress-strain curves and analyzed the tested data. According to the results of tests, by superimposing strain rate strengthering factor and damage weakening factor upon a static constitutive model of concrete-the Ottosen model, the dynamic constitutive model of BFRC was founded. The parameters were confirmed and the model curves were compared with the tested curves. The results show that there is obvious strain rate strengthering effect with the dynamic mechanics performances of BFRC, there are approximate function relation between the dynamic strength increase factor DIF，the peak strain and the strain rate logarithm; the method used to constitute the model is feasible, the theoretical model anastomoses with the tested data well. The constitutive model can be used to describe the impact mechanics behavior of BFRC and can offer important reference for further research and engineering application of BFRC.