Prefabricated building prefabricated concrete stair

The utility model provides an assembly type building prefabricated concrete stair, which relates to the building field, and comprises a fixed base and a fixed top plate, an installation base is installed between the fixed base and the fixed top plate through a fixing assembly, and a stair prefabricated member is installed on the installation base through an assembly assembly. The stair prefabricated parts comprise top prefabricated parts, bottom prefabricated parts and connecting prefabricated parts, the number of the connecting prefabricated parts is multiple sets, and the multiple sets of connecting prefabricated parts are arranged between the top prefabricated parts and the bottom prefabricated parts; the installation base is arranged below the stair prefabricated part, the stair prefabricated part can be fixed and supported by being matched with the assembled guardrail columns, the supporting effect is better, and therefore the structural safety of the stair prefabricated part is better and more stable. 本