PURPOSE: To provide the intake device of a motorcycle by which an air introducing quantity to an engine can be increased without generating any trouble for supply of fuel.

CONSTITUTION: The surrounding of a carburetor 12 is substantially closed with a box 18, the box 18 is connected to the lower stream end part 19b of an air introducing duct 19, and the upper stream end part 19a of the air introducing duct 19 is opened on the front part of a body. Further as a fuel pressurizing means pressurizedly supplying fuel to the carburetor 12, the box 18 and a fuel tank are connected together through a connecting tube 21.