A charged particle beam exposure method is adapted to an exposure apparatus which includes a plurality of exposure systems that simultaneously expose the same pattern. The method includes the steps of (a) generating, by a pattern generating unit in each exposure system, data related to patterns which are to be exposed, (b) deflecting, by a column unit in each exposure system, a charged particle beam onto an object which is mounted on a stage by deflecting the charged particle beam based on the data generated by the pattern generating unit in a corresponding exposure system, and (c) detecting an abnormality in the exposure apparatus during operation of the exposure apparatus based on data which are obtained from corresponding parts of the exposure systems.