The invention relates to a grooving machine for bending machining of an aluminum-plastic plate, and a grooving machining method for the aluminum-plastic plate. The grooving machine comprises a main plate, a reciprocating motion mechanism, a chipping sweeping mechanism, a grooving mechanism and two buffer groove-cutting mechanisms; and the reciprocating motion mechanism is mounted at the right endof the main plate, the grooving mechanism is mounted at the lower end of the reciprocating motion mechanism, the two buffer groove-cutting mechanisms are mounted at the left and right ends of the grooving mechanism, and the chip sweeping mechanism is mounted at the right end of the reciprocating motion mechanism. According to the grooving machine, the problems that in the existing grooving processof an aluminum-plastic plate, manual grooving is needed, when grooving is started , if a grooving cutter directly conducts grooving on the aluminum-plastic plate, the life of the cutter is prone to be influenced, during manual grooving, part of a groove is not formed completely, chipping materials are accumulated on the two sides of the groove during grooving, consequently, the working progress is affected, as for manual grooving, the original position is prone to being deviated, the consumed time is long, the labor intensity is large, and the efficiency is low can be solved, and the functionof mechanical grooving of the aluminum-plastic plate can be achieved.