The invention discloses a detection method for a liquid level alarming switch based on a dynamic liquid level, and a calibration method for an alarming line of a liquid level alarming switch based on a dynamic liquid level. A to-be-detected liquid level alarming switch is arranged on a support, and a float of the to-be-detected liquid level alarming switch is positioned in a liquid storage container. The installed float of the to-be-detected liquid level alarming switch is made to float in liquid, and a liquid level in the liquid storage container is controlled to rise or fall, so the float of the liquid level alarming switch is driven to rise or fall. If the position of an alarming line of the liquid level alarming switch is reached, that is to say, if open and close states of the liquid level alarming switch are converted, an automatic way or a manual way of control is utilized to make changes of the liquid level stop, and then a distance measuring device is adopted to measure calibration parameters of the alarming line of the liquid level alarming switch. In this way, the detection method can directly detect whether the liquid level alarming switch functions normally and also can accurately calibrate the position of the alarming line of the liquid level alarming switch. The detection method provides high precision, and is fast and convenient to operate.