The utility model provides a building slurry mixing all-in-one machine. The building slurry mixing all-in-one machine comprises a feeding hopper, a feeding control box, a stirring kettle, a shell, a bracket and a bag sealing device, the utility model relates to a mixing all-in-one machine for building slurry. Building slurry can be directly used, the utility model relates to non-bearing wall building slurry, in particular to non-bearing wall building slurry taking fly ash and desulfurized gypsum as main raw materials. Mixing from feeding, re-bagging, automation of the entire process, the construction efficiency is greatly improved, the labor cost is reduced, the adding amount of the slurry in each feeding hopper can be accurately controlled, the proportion of the mixed slurry is equal, theaccuracy during slurry proportioning is better ensured, in addition, dust in air during feeding can be reduced to the maximum extent, and good application prospects are achieved.