To provide a water treatment apparatus which is constituted compactly at a low cost and reliably removes sludge contained in raw water.

This water treatment apparatus M is constituted so as to have a stirring part 10 which is arranged on the upper part of a frame 1, a solid- liquid separating part 20 which is arranged on the lower side of the stirring part 10 and a filtration vessel 30 which is arranged on the lower side of the solid-liquid separating part 20 and is surrounded by a side wall part 5 of the frame 1. The stirring part 10 has a blade body 18 stirred by water which is supplied by a water supply port 11 and the solid-liquid separating part 20 is constituted so as to have a roll filter 22 which can be moved in left and right directions by being wound and a cylindrical body 23 which ejects the sludge on the roll filter 22 by means of air. In addition, the filtration vessel 30 comprises five steps of layers and has sliders 34 slidable in back and forth directions and buckets 33 which are placed on the sliders 34 on the respective layers. As the buckets 33, charcoal and natural mineral are used.