The invention provides a bacterium inhibition method and a manufacturing method of heated seafood. The bacterium inhibition method and the manufacturing method can prolong the shelf life of seafood and do not damage the quality and flavor of the seafood. The invention also provides a bacterium inhibition processing liquid used in abovementioned methods. In an antibacterial agent processing step, seafood is contacted with an antibacterial processing liquid containing glucomannan, an antibacterial agent, and water； then the seafood containing the antibacterial processing liquid is heated at a temperature that glucomannan can be gelated； the shelf life of the heated seafood is prolonged, and the quality of the seafood is maintained.
