The present invention provides a kind of root canal filling paste with calcium phosphate bone cement as main material and capable of being stored at certain conditions without change in property and capable of being injected. The root canal filling paste consists of solid powder and curing liquid, the solid powder includes calcium phosphate powder and developing agent, and the curing liquid contains humectant, thickener, coagulant and water. The root canal filling paste compounded with the solid powder and the curing liquid is stored in an injector, and when it is used, the injector with root canal filling paste is set in the air for minutes for the paste to raise its temperature before being injected to root canal. The injected paste will solidify fast to convert into high strength hydroxyapatite. The present invention has less operation steps, shortened surgical operation period and raised root canal treating quality.