PURPOSE: To provide a grizzly-type vibrating screen without the rod-like component contained in a material to be treated being mixed in the undersize.

CONSTITUTION: Semicircular-sectioned undersize transfer troughs 35, 36, 37 and 38 are provided directly below the opening of the screen surface consisting of grizzly bars 31, 32 and 33 to constitute a grizzly unit 10. The unit 10 and the similar grizzly units 20 and 30 are set in a vibrating trough 11, and a gap equal in size to or smaller than the opening is formed between the units 10 and 20. The screening surface of the unit 20 is set at a position lower than the transfer surface of the troughs 35 to 38 of the unit 10. The same positional relation is established also between the units 20 and 30.