The invention discloses a high efficiency cement composite grinding additive, comprising the following raw materials by weight percent: 10-25% of calcined gypsum, 10-30% of calcined aluminite, 20-40% of sodium metasilicate, 2-4% of triethanolamine, 0.5-2% of polyacrylate, 0.5-3% of dispersant and 20-30% of zeolite powder. The preparation method of the high efficiency cement composite grinding additive comprises the following steps: first selecting raw materials, then dripping liquid raw materials-triethanolamine and polyacrylate TH-1100 with a liquid pump in zeolite powder, then preparing reinforced grinding component with a dry powder mixer, finally adding the reinforced grinding component, calcined gypsum, calcined aluminite, sodium metasilicate and dispersant in a kneader to mix for 20-30min and obtaining the product. The product has prominent grinding aid, and can increase the hourly output of mills by 10-15%, reduce the consumption of electricity, and increase the cement 3-day compression strength and the cement 7-day compression strength by more than 20% and the cement 28-day compression strength by 10-15%.