The utility model belongs to the technical field of protection skill training of nuclear radiation and particularly relates to a nuclear radiation shield effect simulation demonstration apparatus, aiming to provide a nuclear radiation shield effect simulation demonstration apparatus which is capable of demonstrating relationship between thicknesses of a radiation shield body and a shield effect. The nuclear radiation shield effect simulation demonstration apparatus is characterized by comprising a light source (1) and a shielding layer, wherein the light source (1) is installed in the shielding layer. By adopting a light source capable of emitting a uniform spectrum and a shielding layer provided with a plurality of shielding layers sequentially sleeved from inside out, simulation of diminishing radioactivity is achieved, and law risks and safety risks caused by adopting a radioactive source during teaching radiation protection are prevented.