A quantitative analysis method of neutron radiography is introduced in the paper. The principle of this method is described

and the influence of scattered neutrons on neutron radiography is analyzed using the particle transport programme MCNP. The relationship between the specimen-detector distance and scattered neutrons is also discussed. To weaken the influence of scattered neutrons

the penetrating thickness of thermal neutrons is quantitatively scaled by analyzing neutron pictures in which internal scattered neutrons have trailed off.