A pattern forming apparatus using lithography technique includes a stage configured to allow a target object to be placed thereon; a plurality of columns configured to form patterns on the target object by using a charged particle beam while moving relatively to the stage; a pattern forming rule setting unit configured to set a pattern forming rule depending on a position of broken one of the plurality of columns; a region setting unit configured to set regions so that unbroken ones of the plurality of columns respectively form a pattern in one of the regions; a plurality of control circuits each configured to control any one of the plurality of columns different from others of the plurality of columns controlled by others of the plurality of control circuits; and a pattern forming data processing unit configured to perform a converting process on pattern forming data for the regions set to output a corresponding data generated by the converting process to the control circuit of a corresponding one of the unbroken ones of the plurality of columns respectively.