The present invention relates to a filtering device for waste plastic extruder easy to remove foreign material, the body being formed of a rectangular case shape, from a front side end portion accommodated in a circular shape in an inward direction is formed in the body, the foreign material on the rear side lower portion of the body this is to remove the waste outlet that is a synthetic resin is discharged is formed, and the receiving portion forming the central portion first inserted into the rear-side direction of the body from the inner side of the ball, receiving portion bore days housing that foreign matter discharge port is formed to be through to the outside direction on the side; Opening and closing door is opened and closed inlet holes formed possibly hinged to the body front side of the housing, so that the waste plastic melt in the central portion flows into the housing; A second insertion hole is formed, the support filter plate from the front side to the rear side direction of the through-hole is formed in a central portion in a plurality of exhaust circular plate shape is coupled is inserted into the receiving portion of the housing; That the second insertion hole is formed, a plurality of fine, which from the front side exhaust ball and the filter plate support mutual face-to-rear direction through hole formed in the central portion to circular plate shape to be inserted into the receiving portion of the housing to be coupled to a front side of the filter plate support filter plate; The rotating shaft is inserted from the first insertion hole of the housing rotates to be inserted in the third insertion hole of the filter plate of the filter plate 2 inserted ball and the support installation; Driving means configured to be connected with one end of the rotating shaft to the rear lateral side of the housing to rotate the rotating shaft; The is coupled to the other end of the rotating shaft to rotate by a drive means for moving foreign matter removal day does not pass through the filter plate and remove the foreign materials remaining on the surface at the same time as a foreign matter discharge port of the housing; Is connected to the foreign matter discharge port of the housing debris being moved flows into the foreign matter discharge port of the housing by the foreign material removing day is discharged to the external foreign matter discharge means provided in the housing on one side; jidoe comprises a, the foreign material removing day "S "and day part is formed in shaped, formed collecting grooves on day negative aspect, the heating wire that generates heat of high temperature inside the housing the waste plastic which is melted inside the inlet to the extrusion without being solidified in the housing is embedded in the body interior of the housing, is connected to the heating coil on the other side of the external housing features a power supply is installed to supply power.