The invention provides an interfacial process for continuous production of polycarbonate resin which is so improved as to give high-quality polycarbonate stably. In producing a polycarbonate resin continuously by interfacial polycondensation of an aqueous alkaline solution of a dihydroxyl compound with carbonyl chloride, a manufacturing plant is used which comprises as the essentials a raw material preparation tank, an oligomerization tank, a polycondensation tank, a washing tank, a resin isolation tank which are connected in series and provided respectively with vent lines, with at least two of the vent lines being independently connected to an exhaust gas treatment unit.