The invention provides a compound red sage root freeze dried powder injection containing salvianolic acid B and its preparing process, wherein the injection comprises root of red rooted saliva, notoginseng and borneol, and is prepared through extracting root of red rooted saliva and notoginseng to obtain red sage root extract, pseudo-ginseng extract, dissolving baras camphor with right amount of ethanol, coating with beta-cyclodextrin, charging injection for water into red sage root extract, notoginseng or red sage root and notoginseng extracts for dissolving, boiling, cooling down, filtering, mixing filtrate with baras camphor beta-CD inclusion solution, charging mannitol, adding right amount of water for injection, adjusting pH, and freeze-drying. In the obtained freeze dried injection, calculated by salvianolic acid B (C36H30O16), the content of red sage root 6.25-100.00mg/g freeze-dried powder solid.