Hydroxyapatite (HAP) and calcite (CAL) particles are bioactive materials and can promote the mineralization of hard tissue in oral cavity, having broad application in oral care products.This in vitro experiment study investigates the efficacy of simulated oral fluid (SOF), toothpaste 1 containing 8.0 % micro CAL, toothpaste 2 containing 2.0 % nano HAP and 6.0 % micro CAL, toothpaste 3 containing 4.0 % nano HAP and 4.0 % micro CAL and toothpaste 4 containing 8.0 % nano HAP on the repair of demineralized enamel surface and demineralized dentine surface respectively.The results show that among treatments, the toothpaste 3 can increase the Vickers micro hardness of demineralized enamel surface to the most and dramatically decrease the diameter size of tubules on the demineralized dentine surface to the smallest, indicating the best repair efficacy and its promising application in oral care.The research also discusses the process and mechanism of the toothpaste containing nano HAP and micro CAL repairing the demineralized enamel surface and demineralized dentine surface.