The invention discloses roller compacted concrete fine mixing and adding equipment and method. The equipment is composed of a vehicle body walking mechanism, a hydraulic power system, an automatic slurry control supply system, a variable-amplitude multi-level stirring shaft system, a slurry flow control system, an accurate satellite positioning system and a far-end informatization monitoring platform. The method depends on the development of a concrete mixing and adding system, even permeation of distorted concrete slurry is ensured through the rotary mixing mode, and visualization of the adding quality of a storehouse surface is achieved through a positioning and metering information communication feedback system. The roller compacted concrete fine mixing and adding equipment and method can clearly reflect whether the adding position and grouting amount meet the requirements or not, and field adding management is convenient.