A hot-air supply structure (1) comprises a hot air generator (20) and a housing (15) formed in the neighborhood of a hot-air inlet (81) of a molded component M in a die (10). A nozzle (21) is formed at the forward end of the hot-air generator, and an ejection port (211b) is formed on the side wall portion of the forward end needle unit (211) of the nozzle. The housing includes a support hole (151) in the nozzle, a relief hole (152), a flow path communication passage (153) and a bypass (154). The ejection port is movable between a first position to discharge the cool or warm air into the atmosphere through the bypass from the relief hole and a second position to introduce hot air into the flow path (8) of the molded component through the inlet (81) and the passage (153).