The invention discloses a vacuum insulation plate and a manufacturing method thereof. The vacuum insulation panel comprises a closed hollow cavity body which is formed by casting a material slurry, wherein the interior of the cavity body is hollow; an airtight layer is arranged on the inner wall or/and the outer wall of the cavity body. After the cavity body is vacuumized, convective heat transfer caused by air movement can be avoided, so that the thermal insulation is excellent; the vacuum insulation plate is formed by casting concrete or the material slurry, so that the vacuum insulation plate is firm and reliable; a basic material adopts the concrete or the material slurry with high strength, and the strength is high enough to bear long-term effects of a vacuum pressure, a wind load, self weight and a temperature deformation stress; more than 90% of the plate structure is made of cement and other inorganic materials, so that the long service life of the vacuum insulation plate can be ensured; the vacuum insulation plate mainly uses vacuum, the cement, pottery sand and other low-cost materials, so that the cost of the vacuum insulation plate disclosed by the invention is only 1/3 that of the conventional vacuum insulation plate; 90% of the plate structure is made of the cement and the pottery sand, so that the fire-proof performance is class A; the vacuum insulation plate is applicable to external wall insulation and roof insulation for buildings with a shear wall structure, a framework structure and a steel structure.