Provided are a method and apparatus for verifying a radiation beam intensity modulator. The apparatus includes a scanner； and a verification system verifying the verification target radiation beam intensity modulator, wherein the verification system includes: a modulator structure reconstruction unit extracting thickness information of the verification target radiation beam intensity modulator based on the 3D structure information of the verification target radiation beam intensity modulator； an original modulator structure information receiver receiving structure information of the original radiation beam intensity modulator； a modulator matching unit matching the verification target radiation beam intensity modulator with the original radiation beam intensity modulator based on the thickness information； and a modulator verification unit verifying the verification target radiation beam intensity modulator matched with the original radiation beam intensity modulator.
