To provide a fuel injection control method for an internal combustion engine suppressing the generation amount of soot.

A diesel engine 10 is provided with a main fuel injection valve 17 for injecting a main fuel, and a secondary fuel injection valve 18 for injecting a secondary fuel which is smaller in soot generation amount than the main fuel. An ECU 30 calculates the injection amount of the main fuel in response to engine load. When the injection time of the main fuel corresponding to the injection amount calculated by the ECU 30 exceeds a predetermined one, the main fuel injection by the injection valve 17 is stopped, and the secondary fuel in the amount corresponding to that of the main fuel to be injected after the predetermined time elapse is injected through the injection valve 18.