采用蒙特卡罗程序MCNP模拟计算了医院中子照射器I型堆（IHNI-1）热中子束流孔道出口处的等效平面源。对B堆芯进行了临界搜索计算，模拟计算了热中子束流孔道及出口处中子、γ的束流参数，应用等效平面源模型建立了BNCT等效中子、γ平面源。为人体头颅等效模型剂量分布的快速计算提供了较为可靠的平面源。

Numerical calculation for the equivalent surface source of the thermal neutron duct of in-hospital neutron irradiator mark 1(IHNI-1) reactor is carried out using MCNP Monte Carlo code. Cold clean criticality of B core is searched. Neutron beam parameters at the exit of thermal neutron duct are calculated. Equivalent neutron and γ surface sources for BNCT are built using equivalent surface source model. And these sources are reliable to calculate absorbed dose distribution in equivalent model of head quickly.