The invention discloses a method for efficiently concentrating polycarbonate. The method for efficiently concentrating the polycarbonate comprises the following specific steps that a, a polycarbonateresin solution enters into a preheater for being heated for first concentration, and the solvent content in the solution is 88-92%; b, a material enters into a film evaporator for secondary concentration, the solvent content in the polycarbonate resin solution is 88-78%, and a vaporized solvent enters into a cooler for cooling and recycling; c, then the vaporized solvent enters into a buffer tank,control flow is 100%-300% of that entering into the preheater, and the solvent content is 83-78%; and d, the polycarbonate resin solution joining with the upstream process through a transfer pump enters into a mixer, the step a is repeated, internal circulation is carried out, and the solvent is further removed. The polycarbonate resin solution is concentrated by adopting an internal circulationcompound mode of ''the preheater and the film evaporator'', the process is compact and concise, and the effect of removing the solvent is good. An on-line concentration meter is matched at an outlet to detect the resin concentration in real time, so that the resin concentration is fed back to on-line concentration detection timely, and the process controllability is high.