The invention discloses a warm mixing and antiflaming asphalt mixture, and further discloses a preparation method thereof as follows: first, inert filler and heated gravel are put into a stirring cylinder to be drily mixed for more than 5 seconds, then heated asphalt is poured into the stirring cylinder, and organic thinner visbreaker and efficient compound type flame retardant are added in the stirring cylinder to be stirred so as to uniformly cover the gravel until the gravel is completely covered by the asphalt without any grey material; and the factory inspection temperature of the mixture is controlled between 135 to 140 DEG C so that the warm mixing and antiflaming asphalt mixture is obtained. Compared with the common asphalt, the asphalt mixture prepared by the invention not only has better high-temperature performance, ageing resistance, temperature sensibility and the like, but also has good heat insulation effect, no melting drippage, no thermal contraction and limited oxygen index larger than 32, adds organic thinner visbreaker so as to make the warm mixing and antiflaming asphalt mixture integrate the advantages of the flame retardant and warm stirring retardant into a whole, and is more beneficial to being promoted and applied on asphalt road surfaces.