According to one embodiment, a charged particle beam writing apparatus includes, a writing mechanism, a writing control circuit, a deflection operation control circuit configured to generate control data for controlling the blanking of each of the charged particle beams based on the shot data, a storage, a blanking control circuit configured to control the blanking based on the control data, and a detector. The writing control circuit is configured to, when the detector detects the abnormality during the writing, interrupt the writing, and generate interrupt position information at a position where the writing is interrupted based on the shot data which has been stored at the storage and is related to the control data that has not been used for controlling the blanking.