The engine controller includes: an engine-rpm increase amount computing section for computing an amount of increase in an engine rpm, generated by first ignition of an engine after a restart condition is satisfied; a start failure determination crank-angle change amount determination value setting section for setting a restart failure determination threshold value based on the amount of increase in the engine rpm; and a restart failure determination section for determining a restart failure when a crank-angle change amount from a first ignition timing of the engine after the satisfaction of the restart condition becomes larger than the restart failure determination threshold value although a complete combustion of the engine is not determined, interrupting a restart operation of the engine, and restarting the restart operation of the engine after elapse of a predetermined period of time.