NOVELTY - Biogas fermentation system comprises a fermentation tank body, a water drain pipe and a gas plate. The fermentation tank body is set with a fermentation chamber. The left and right two side walls of the fermentation tank body correspond to fermentation chamber which are mutually connected to a feedstock port and a discharge port. The side wall of the fermentation tank is connected to a water pressure unit by a pipe. The top peripheral portion of gas plate is provided with an opening located at lower end of gas plate. A support device is fixed in fermentation chamber by gas plate.    USE - Used as a biogas fermentation system.    ADVANTAGE - The system promotes high turbulent flow efficiency of biogas liquid.    DETAILED DESCRIPTION - Biogas fermentation system comprises a fermentation tank body, a water drain pipe and a gas plate. The fermentation tank body is set with a fermentation chamber. The left and right two side walls of the fermentation tank body correspond to fermentation chamber which are mutually connected to a feedstock port and a discharge port. The side wall of the fermentation tank is connected to a water pressure unit by a pipe. The top peripheral portion of gas plate is provided with an opening located at lower end of gas plate. A support device is fixed in fermentation chamber by gas plate. There is gap located between the upper- and lower- part side walls of gas plate and the upper- and lower- side walls of fermentation tank body. An inlet of the gas plate is located along the sidewall of an air inlet resistance plate. The gas plate is connected to a gas discharge port blocking plate located close to the side wall of the discharge port. There are multi-baffles located between the inlet air resistance plate and an outlet block of gas plate. A first fermentation area is located between air inlet block areas set adjacent to a baffle plate. A second fermentation area is located between adjacent baffle plates. A third fermentation area is located in adjacent area between gas discharge port blocks. The upper part of each fermentation area is provided with a separate airway set with a drain pipe comprising a first area drain pipe, a second area drain pipe and a third area drain pipe. The first area drain pipe is located opposite to the first fermentation area. The second area drain pipe is located opposite to the second fermentation area. The third area drain pipe is located opposite to the third fermentation area. The fermentation system further comprises a pulling rod, a transverse rod and a vertical rod. The vertical rod along the vertical direction is connected to one end of the transverse rod. A gap is located between fermentation chamber and vertical rod which is located between two storage plates and fermentation tank body. The first fermentation area is provided with a water drain control pressure pipe located inside the fermentation chamber allowing unidirectional flow of biogas slurry into a one-way valve. The second fermentation area is provided with a water drain control pressure pipe located inside the fermentation chamber allowing unidirectional flow of biogas slurry into a one-way valve. The liquid flows from lowest level of the third area drain pipe into highest level of first area drain pipe and lowest level of the second area drain pipe.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic representation of the biogas fermentation system.