The invention relates to a method for reducing the loss of fragrant substances of reconstructed tobaccos in the concentration process. The method comprises the following steps of: concentrating a tobacco water extracting solution obtained by an extraction working section in the process of producing the reconstructed tobaccos by a papermaking method; mixing polyhydric alcohol and the tobacco water extracting solution in a weight ratio of 1:10-1:100 uniformly in a concentration working section, and adding the mixture into concentration equipment; and concentrating at concentration temperature of between 45 and 100 DEG C under the concentration condition that the vacuum degree is 0.04 to 0.08 MPa until tobacco paste of which the density is 1.220+/-0.005 is obtained. By the method, the quality of coating liquid can be improved effectively, so that the quality of the reconstructed tobaccos is improved, and tobacco discarded raw materials can be utilized fully and reasonably.