he invention relates to a foam cement insulation board and a preparation method thereof, and provides a foam cement insulation board containing industrial solid wastes and a preparation method thereof. The foam cement insulation board is composed of a mixture A and a mixture B. The mixture A comprises 55-65% of cement, 10-20% of gypsum powder, 8 -15% of hydrogen peroxide,3-4% of a flocculant, 1-2% of a water reducing agent, 1-2% of a coagulant, 2-3% of a cement waterproof agent, 1-2% of lithium carbonate, 1-2% of fiber, and 1-2% of solid master batch. The mixture B comprises 35-47% of a base material, 35-39% of a magnesium chloride solution, 10-15% of magnesium oxide, 2-5% of a binding agent, 2-3% of industrial hydrogen peroxide, 1-2% of lanthanide rare earth and 5-7% of an additive. The Foam cement insulation board provided by the invention has advantages of fireproof, waterproof, light weight, compressive and flexural resistance and high strength, and effectively utilizes industrial solid waste, facilitates environmental protection, and truly realizes turning wastes into treasures.