Abstract: The boundary flow response matrix (BFRM) method can get good precision in 2D reactor core calculation with much less CPU time. The calculation speeds of BFRM method and transport calculation were compared and the calculation time for different numbers of grids using the BFRM method was investigated, which shows the advantage of BFRM method in term of calculation speed. In order to improve the precision of pin power distribution, the shape factor correction method and the characteristic boundary flow response matrix (CBFRM) method were introduced. The shape factor correction method can improve the cell power precision partly, while the CBFRM method based on reflective boundary conditions is more potential in further research.