The utility model relates to a cleaning tool, more specifically says and relates to a novel mop, is provided with sliding block and round brush, and when reciprocating the sliding block, the round brush can clean and dewater the rag, makes the cleanness and the dehydration of rag obtain the simplification, has improved the efficiency of dragging ground. The upper end at the mop pole is installed to the mop head. Go up the holding ring and fix the centre at the mop pole. The sliding block is installed in the centre of mop pole, sliding block and mop pole swing joint. Hinge I fixes the lower extreme at the sliding block. The lower extreme at hinge I, bracing piece and hinge I swing joint are installed to the bracing piece. The lower extreme at the bracing piece, round brush and bracing piece swing joint are installed to the round brush. The lower extreme at the mop pole is fixed to the holding ring down. Hinge II fixes the lower extreme at the mop pole. The lower extreme at hinge II, mop board and hinge II swing joint are installed to the mop board. The rag is installed on the mop board to be located the lower extreme of mop board.