The invention relates to the field of heat insulation of outer walls, in particular to an outer wall inorganic heat insulation material system. The outer wall inorganic heat insulation material system comprises an interface layer, a waterproof anti-cracking layer and an inorganic active heat insulation layer, wherein the interface layer is made of interface mortar; the inorganic active heat insulation layer is made of an inorganic active heat insulation material; the waterproof anti-cracking layer is made of waterproof anti-cracking mortar; the inorganic active heat insulation material comprises cement, water-repellent vitrified micro beads, a tackifying water retaining agent, dispersible latex powder, first chopped fibers, and ore slag powder; the interface mortar comprises cement, quartz sand, dispersible latex powder, and a tackifying water retaining agent; the waterproof anti-cracking mortar comprises cement, quartz sand, a mineral additive, a tackifying water retaining agent, dispersible latex powder, second chopped fibers, and triple superphosphate powder. The outer wall inorganic heat insulation material system provided by the invention has the advantages that the weather-resistant property is good, the shrinkage rate is low, and the heat insulation effect is good.