Abstract: The neutron leakage multiplication in vanadium sphere with DT neutron is measured using the total absorption method. A polyethylene sphere with an outer radius of 69 cm is used as the total absorption detector (TAD). A 6Li glass detector is used to measure the radial distributions of neutron count rate in the TAD. This detector has the same 1/V characteristic absorption to thermal neutrons as element H. The distributions of reaction rate of threshold detectors Al, Fe, In, V in vanadium sphere, are measured using 14 MeV neutron source. The neutron multiplication and reaction rate are calculated using MCNP/4A code with ENDF/BⅥ and FENDL2 library data. The measured results are compared with the calculated. The calculated result by ENDF/BⅥ library data coincides with the measured results. However the calculated value with FENDL2 library data is about 4% larger than the measured.