A security inspection system and a security inspection method. At least one inspection subsystem performs a ray scan on an inspected object to produce ray image data of the inspected object (S410); at least one local computer is communicatively connected to the inspection subsystem to store the ray image data; the local computer divides the ray image data into multiple subareas according to a predefined mode (S420); image data of the subareas respectively are stored according to columns, and information expressing relations between the subareas also is stored (S430).