Abstract: The present invention provides a liquid level detection device for detecting the liquid level height of liquid fuel in a chamber, which has an inner space connected with the chamber. The liquid level detection device comprises: a heater, which is configured in the inner space of the liquid level detection device, and is used to heat the liquid fuel in the inner space; at least one temperature sensors, which are configured in the inner space of the liquid level detection device, and is used to measure the temperature of the liquid fuel in the inner space; and, a liquid level calculation device, which receives the temperature signals of the liquid fuel measured by these temperature sensors, and calculates the temperature variation rate of the liquid fuel, and converts into the liquid level height of the liquid fuel in the chamber according to the temperature variation rate.