To prevent black smoke emissions in accelerating by avoiding excessive feeding of fuel for acceleration, in a carburetor with an acceleration pump.

This carburetor 1A with the acceleration pump is provided with the acceleration pump 3 which, when an engine is accelerated, delivers fuel to the inside of an intake passage 2 from an acceleration fuel chamber 30 storing the fuel introduced from a constant fuel chamber 4 and feeds the fuel for acceleration to the engine. In the carburetor, a cutoff valve 5A as an acceleration fuel feeding stop means is provided for stopping feeding of the fuel for acceleration under the condition of more than a previously set temperature.