The method for distinguishing between prostate carcinoma and benign prostatic hyperplasia comprising: bringing an analyte sample containing a prostate-specific antigen (PSA) into contact with a carrier having an anti-free PSA antibody immobilized thereon, thereby binding free PSA to the anti-free PSA antibody immobilized on the carrier; thereafter bringing the carrier in which the free PSA is bound to the immobilized anti-free PSA antibody into contact with a monoclonal antibody capable of specifically recognizing a glycan in which a terminal sialic acid residue is bound to galactose through an α(2,3) bond, thereby binding the monoclonal antibody recognizing the glycan to the free PSA bound to the anti-free PSA antibody; measuring the amount of the free PSA having an N-type glycan in which a terminal sialic acid residue is bound to galactose through an α(2,3) bond; comparing the measured amount thus obtained with a preset cutoff value for prostate carcinoma and benign prostatic hyperplasia, thereby determining that when the measured amount is larger than the cutoff value, prostate carcinoma is developed or the probability of developing prostate carcinoma is high, and when the measured amount is smaller than the cutoff value, benign prostatic hyperplasia is developed or the probability of developing benign prostatic hyperplasia is high.