The instantaneous interruption detection apparatus includes a noise removing section to remove a noise component from an in-cylinder pressure signal inputted thereto, and output a noise-removed in-cylinder pressure signal, a derivative signal calculating section to calculate a detection signal which is a function of a derivative value of the noise-removed in-pressure signal with respect to the crank angle of an internal combustion engine, an instantaneous interruption determining section configured to make determination that instantaneous interruption of the in-cylinder pressure signal has occurred when the detection signal has exceeded a detection threshold, and a threshold setting section configured to set the detection threshold to such a value that the instantaneous interruption determining section can make the determination in accordance with the noise-removed in-pressure signal which is dull compared to the in-cylinder pressure signal inputted to the noise removing section depending on a gain-frequency characteristic of the noise removing section.