A method of dividing a wafer whose strength is reduced along a plurality of dividing lines formed on the front surface in a lattice pattern, along the dividing lines, comprising: a tape affixing step for affixing a protective tape to one surface side of the wafer; a holding step for positioning a first suction-holding member and a second suction-holding member on both sides of a dividing line and suction-holding the wafer on the first suction-holding member and the second suction-holding member through the protective tape; and a dividing step for moving the first suction-holding member and the second suction-holding member in a direction for separating them from each other to exert tensile force in a direction perpendicular to the dividing line.