To effectively suppress an intense knock and improve reliability of an engine. A method for predicting occurrence of a knock with a predetermined intensity or higher (intense knock) in an engine 1 that burns an air-fuel mixture of gasoline fuel is provided. Pressure in a combustion chamber 17 (cylinder inner pressure) is detected in an initial stage of combustion. The cylinder inner pressure is compared with a preset reference value SV to determine whether or not the cylinder inner pressure exceeds the reference value SV during the course of the combustion. When the cylinder inner pressure exceeds the reference value SV, it is predicted that the intense knock occurs before an end of the combustion.