The theoretical and experimental studies on BaSi2/Si heterojunction solar cells have demonstrated the great potential in utilization of BaSi2 material as light absorption layer for developing high efficiency solar cells with low cost. In addition to BaSi2/Si heterojunction solar cells, BaSi2 based Schottky junction solar cells could also be achieved by coupling n-type or p-type BaSi2 with suitable metal electrode. In this work, BaSi2 based Schottky junction solar cells were simulated with the program AMPS (analysis of microelectronic and photonic structures)-1D in order to thoroughly understand the mechanism for further improvement in conversion efficiency. Simulation results demonstrated that a simpler structure of metal/n-BaSi2 Schottky junction solar cell with thickness of 2000 nm can reach high conversion efficiency up to 24.12% and 25.28% for N-D = 1 x 10(15) cm(-3) and N-D = 1 x 10(18) CM-3 respectively, being comparable to BaSi2/Si heterojunction solar cell. Contact barrier height, illumination condition, as well as defect level of metal/n-BaSi2 Schottky junction solar cell were also identified to significantly influence the device performance.