The invention provides a generator and a control method of the generator. The generator comprises a shell, a water inlet system and a controller. A combustion chamber and a steam chamber are formed inthe shell, an outlet channel is arranged at the upper end of the shell, a first temperature sensor is arranged in the outlet channel, an air inlet and a fuel inlet are arranged at the lower end of the shell, the air inlet is provided with an air valve, and the fuel inlet is provided with a fuel valve; the water inlet system comprises an upper water inlet mechanism, a lower water inlet pipeline and a return water pipeline, the upper water inlet mechanism is provided with an upper water inlet valve, the lower water inlet pipeline is provided with a lower water inlet valve, and the return waterpipeline is provided with a second temperature sensor and a flow control valve; and the controller is electrically connected with a liquid level meter, the first temperature sensor, the air valve, thefuel valve, the upper water inlet valve, the lower water inlet valve, the second temperature sensor and a backflow water flow control valve. The liquid level of cooling water in a containing cavity can be accurately measured and controlled while the combustion chamber is stably combusted, so that the temperature of output multi-component hot fluid can be effectively controlled.