The invention discloses a basalt fiber anti-cracking coating and a preparation method thereof. The basalt fiber anti-cracking coating is prepared from the following raw materials in percentage by mass: 1 percent of basalt fiber, 20 percent of waterborne fluorocarbon emulsion, 10 percent of silica sol, 60 percent of sand, 1 percent of thickening agent, 1 percent of mildew preventive, 2 percent of silane waterproofing agent and the balance of water. The preparation method of the basalt fiber anti-cracking coating comprises the following specific steps: I, raw material preparation; II, stirring;III, blending. The basalt fiber anti-cracking coating has the advantages of wide raw material source, simple preparation process and low investment cost on production equipment; the basalt fiber is added in the coating, so that the strength is enhanced effectively; the basalt fiber anti-cracking coating also has the excellent performance of electric insulation, corrosion resistance and high temperature resistance; the waterborne fluorocarbon emulsion is taken as a main film forming material of a waterborne fluorocarbon coating, so that the basalt fiber anti-cracking coating has excellent weather resistance, water resistance, pollution resistance and chemical resistance; the basalt fiber anti-cracking coating has the advantages of dirt resistance, dust resistance, aging resistance, fire retardancy, permeability, waterproof layer and excellent cracking resistance.