The invention discloses a device for evaluating receiving quality of a digital communication system, which comprises a receiving processing unit, a receiving information resolving unit and a receiving quality evaluation unit, wherein the receiving processing unit is used for performing synchronization, decoding and error rate calculation on the receiving data of a receiving end of the digital communication system, and outputting synchronous mark and error rate; the receiving information resolving unit is used for judging the error type of the receiving data which finish synchronization and have error codes according to the synchronous mark and error rate output by the receiving processing unit; and the receiving quality evaluation unit is used for evaluating the receiving quality of the receiving data according to at least one of the error type, the error rate and the synchronous mark. The device can accurately and comprehensively evaluate the receiving quality of the digital communication system under the condition of different errors, and solves the problem of evaluation one-sidedness of the receiving quality in the prior art. The invention also provides a method for evaluating the receiving quality of the digital communication system.