An ammonia water desulfurization system comprises a cylindrical shell (1), a desulfurization section and an absorption section, the absorption section is located above the desulfurization section, andthe desulfurization section comprises a double-nozzle bidirectional spraying device (2) arranged in the shell (1) and bilateral blowing devices (3) symmetrically arranged on the inner wall of the shell (1); the absorption section comprises an air inlet cylinder (20), an annular honeycomb-shaped flow equalizing plate (21) and a leaching spray head (23); the utility model has the advantages that: the utility model has the advantages of simple structure; a double-nozzle two-way spraying device and a double-side blowing device arranged in a shell are arranged; atomized ammonia water can be uniformly distributed in the shell and is fully absorbed by sulfur dioxide in the flue gas; the annular honeycomb-shaped flow equalizing plate of the absorption section enables gas absorption to be more thorough, the sprayed liquid is concentrated into the liquid accumulation groove through the semispherical flow guide plate at the top of the gas inlet cylinder and then discharged into a solution at thebottom of the desulfurization tower through the liquid guide pipe, and the situation that the upper-layer spraying liquid influences the lower-layer primary desulfurization spraying effect is avoided.