The invention discloses a microscopic displacement experimental system based on a CT digital core. The experimental system comprises a core holding unit and microscopic displacement equipment, wherein the core holding unit comprises an inlet end, an outlet end, a core area and a shell; the shell is made of polyether-ether-ketone PEEK; the microscopic displacement equipment comprises an oil phase intermediate container and a water phase intermediate container connected in parallel and is used for displacing constant-flux pumps of the oil phase intermediate container and the water phase intermediate container; the liquid outlet ends of the oil phase intermediate container and the water phase intermediate container are connected with the inlet end of the core holding unit; the core holding unit is used for pressurizing the core clamped in the core holding unit by virtue of a hand pump; and a metering bottle is arranged at the outlet end of the core holding unit. The system disclosed by the invention is applied to small-capacity small-scale microscopic displacement experiments, and compared with the traditional displacement experimental equipment, the technical equipment is high in operating precision and measurement accuracy.