The invention discloses a grinding device for sapphire wafers. The grinding device for sapphire wafers comprises a pulp stock barrel, a peristaltic pump and a grinder, wherein a pulp stock trough is arranged on the grinder, and pulp stock enters into the grinder through the peristaltic pump and the pulp stock trough. The grinding method for the sapphire wafers comprises the following steps: 1, preparing the pulp stock: putting in raw materials by levels and layers; 2, controlling pulp stock flows: putting pulp stock accurately; 3, correcting the flatness of the surface of a grinding lower plate: repeatedly measuring by using a long gauge, a short gauge and a dial gauge, and correcting; 4, distributing powder on the surface of a grinding plate; and 5, grinding both sides of each wafer: firstly carrying out light pressing grinding. The grinding method provided by the invention is characterized in that raw material ratio of the pulp stock is optimized, the pulp stock supplying flow is more accurate, the conveying is more even, before normal grinding, light pressing grinding is performed firstly, the problem of wafer breakage during a grinding process can be prevented for the greatest possible, the wafer breakage rate is lowered, the merit factor of grinding is improved, the removing rate during grinding is stable, the problems of over grinding and low removing rate cannot be caused, and the efficiency is relatively high.