In order to get an Epithermal neutron radiation field for the using of Boron neutron capture therapy(BNCT),based on the Tsinghua University experimental reactor neutron source,the research pro- posed two engineering schemes through MC simulating method.In the end the differences between the two schemes were analyzed and contrasted,and the result showed that Scheme 1 is superior to Scheme 2,which was consequently selected for the BNCT system.