The plastic scrap extruding apparatus has a simple structure and is capable of suitably crushing plastic scraps and sending them to a heating cylinder 10. The extruding apparatus comprises: a housing 12 holding a rear part of the heating cylinder 10 and having a material inlet 13; a large rotary blade 20 for crushing the plastic materials and rotatable with a screw 11; small rotary blades 21, 22 being located on the axially front and rear sides of the large rotary blade 20 and rotatable with the large rotary blade 20; and a fixed blade 30 being fixed to the housing 12 and capable of working with the rotary blades. A large rotary blade 20 passable groove 40, through which the large rotary blade 20 can be rotated, is formed in a lower part of the housing 12.