NOVELTY - An organic wastewater processing apparatus (101) comprises methane fermentation processing tank (10) which performs methane fermentation treatment of organic wastewater (1), reaction tank (20) of dipping type which performs aerobic-organism process of methane fermentation treated water (2), and solid-liquid separator (30) which separates liquid mixture (3) in reaction tank into solid and liquid. The methane fermentation processing tank has cover part which prevents diffusion of dissolved methane in air and supply part which supplies methane fermentation treated water to reaction tank.    USE - An organic wastewater processing apparatus for sewage and industrial wastewater.    ADVANTAGE - Methane dissolved in methane fermentation treated water can be processed easily without diffusing in air, preventing contribution to global warming.    DETAILED DESCRIPTION - An organic wastewater processing apparatus (101) comprises methane fermentation processing tank (10) which performs methane fermentation treatment of organic wastewater (1), reaction tank (20) of dipping type which performs aerobic-organism process of methane fermentation treated water (2), and solid-liquid separator (30) which separates liquid mixture (3) in reaction tank into solid and liquid. The methane fermentation processing tank has cover part which prevents diffusion of dissolved methane in air and supply part which supplies methane fermentation treated water to reaction tank, maintaining the state which prevents diffusion of dissolved methane in air. The reaction tank has aerobic tank which performs aerobic-organism process and anaerobic tank which performs denitrifying process. The supply part supplies methane fermentation treated water to anaerobic tank and is downstream of methane fermentation processing tank. A dissolved methane collection tank is provided upstream of reaction and is a gas blowing-in apparatus which blows in gas of carbon dioxide, nitrogen, air, and/or inert gas into methane fermentation treated water and has supply part which supplies methane gas collected by blow-in of gas to anaerobic tank. An INDEPENDENT CLAIM is included for organic wastewater processing method.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of organic wastewater processing apparatus. (Drawing includes non-English language text).    Organic wastewater (1)    Methane fermentation treated water (2)    Liquid mixture (3)    Methane fermentation processing tank (10)    Reaction tank (20)    Solid-liquid separator (30)    Organic wastewater processing apparatus (101)