PURPOSE: To provide a method for manufacturing a fiber reinforced structure by adding a long fiber and a short fiber in a resin pellet previously.

CONSTITUTION: When a fiber reinforced structure which contains reinforcing long and short fibers is to be,manufactured in a thermoplastic resin pellet, a plurality of continuous reinforcing fibers are passed through a melt of a thermoplastic resin in which at least one kind of reinforcing short fiber is mixed. To this reinforcing continuous fiber, the thermoplastic resin melt which contains the reinforcing short fiber is stuck, which is cut into a long fiber longer than the reinforcing short fiber so as to make a pellet.