This research deals with an object-oriented task description(OOTD) method to solve problems such as being hard to understand and a lack of description in existing task description methods. The OOTD method includes an object-oriented task structure diagram and an object-oriented task attribute diagram. The former shows some relationship between a task and a derived task. The latter includes important attributes to define each task. Finally, a sample case is introduced to show how efficient these two diagrams are for the task description.