To reduce raking residue by a simple structure around a separation part where a rake-mounting part of a chain is moved onto a sprocket and a rake is separated from a screen.

A laterally-raking-type dust remover 1 to be installed in a water channel includes the screen 3 comprising screen bars 3A arranged vertically in parallel, and the rake 8 attached to a drive chain 7 for raking the residue in a manner of passing through the screen bars 3A. The rake 8 is separated from the screen 3 on the way from a first passage S1, where the rake-mounting part 7A extends along the screen 3, to a second passage S2 on the drive sprocket 5. In the dust remover 1, a projection 18 is formed on the screen 3 as a rake-retreating means 17 to allow the rake 8 to retreat from a front edge 3B of the screen 3 when the rake-mounting part 7A is positioned on the first passage S1.