A task changing apparatus changes a task program executed by a robot. The task changing apparatus includes: a storage unit that stores a task program including a plurality of hierarchical levels arranged in a tree-like structure representing a plurality of pieces of task information executed by the robot and lower-order task information associated with the task information; a display control unit that causes the task information to be displayed on a display screen of a display unit so as to allow setting of the task information, the task information being associated with each other for each hierarchical level of the task program stored in the storage unit; and a change unit that changes the task program for the robot based on a series of pieces of task information set on the display screen of the display unit.