The invention relates to an airship capable of automatically adjusting the flight attitude and an attitude adjustment method thereof. The airship comprises an airship body airbag which is internally provided with a trimming robot, a trimming robot maintaining device and a sensor. The trimming robot is located near the theoretical gravity center of the airship and connected with the sensor and can receive a signal of the sensor. The sensor is used for monitoring the flight attitude of the airship. The trimming robot maintaining device is used for maintaining the trimming robot to operate towards one side of the theoretical gravity center along a fixed route. The trimming robot automatically moves along the trimming robot maintaining device in the airship body airbag and achieves re-trimming on the airship through the self-weight. According to the airship capable of automatically adjusting the flight attitude, propelling devices at the tail or on the two sides of the airship are simplified, and great significance is achieved for airship structural weight reduction and airship effective load increase.