A pulse combustion device wherein pulse combustion of a rich mixture of primary air and gaseous fuel is established without provision of conventional non-return valves. The pulse combustion device includes a housing forming therein a combustion chamber, a spark plug mounted on the housing and having an electrode located in the combustion chamber, an air intake nozzle plate formed with at least one air intake port and fixedly coupled within the housing to form an air intake chamber in open communication with the combustion chamber through the air intake port, at least one gas intake nozzle coupled with the air intake nozzle plate to admit a rich mixture of primary air and gaseous fuel under pressure therethrough into the combustion chamber, and a baffle plate secured in place within the housing at a position spaced from an inside surface of the air intake nozzle plate with a predetermined clearance in such a manner as to cover the air intake port and gas intake nozzle, the baffle plate being formed smaller in diameter than the housing to form an annular passage in open communication with the combustion chamber, and an electrically operated blower arranged to forcibly supply secondary air therefrom into the air intake chamber.