The invention provides an endurance life test device and method for a liquid level meter. The endurance life test device comprises an inner liquid tank, an outer liquid tank, liquid return pipelines,a liquid outlet pipeline, liquid level switches, a counter and a controller. The inner liquid tank is equipped with a floating-ball continuous liquid level meter. A first liquid level switch is installed at the position, as high as a movement upper limit position of the liquid level meter, in the inner liquid tank. A second liquid level switch is installed at the position, as high as a movement lower limit position of the liquid level meter, in the inner liquid tank. First ends of the liquid return pipelines stretch into the inner liquid tank. Second ends of the liquid return pipelines are arranged between outer wall of the inner liquid tank and the inner wall of the outer liquid tank. The liquid return pipelines are equipped with liquid return pumps. The liquid outlet pipeline is connected to the inner liquid tank and equipped with a valve and a liquid outlet pump. The two liquid level switches, the liquid return pumps, the liquid outlet pump, the valve and the counter are all electrically connected with the controller. With the device and the endurance life test method of the device, an endurance life test of the floating-ball continuous liquid level meter is achieved. The test efficiency and reliability are high.