Metakaolin waterborne suspension liquid, preparation method and application of suspension liquid and cement paste for well cementing in oil field

The invention provides metakaolin waterborne suspension liquid which comprises the following raw materials: metakaolin, a dispersant, a suspension stabilizer, a microbicide and de-ionized water, wherein based on the weight of the metakaolin, the weight percentages of the dispersant, the suspension stabilizer, the microbicide and the de-ionized water are 0.1%-1%, 0.1%-0.5%, 0.1%-0.3% and 100%-112% respectively. The invention further provides a method for preparing the metakaolin waterborne suspension liquid and cement paste for well cementing in an oil field. The metakaolin waterborne suspension liquid provided by the invention is high in solid content, low in viscosity and stable to store.