A new PCR method, PCR-CTPP (polymerase chain reaction with confronting two-pair primers) was invented to genotype a relatively large number of samples in a cost-effective and time-saving manner. In this method, allele-specific DNA products are amplified by means of applying appropriately designed two-pair primers (four primers) into an ordinary PCR tube. Single genotyping for G2886T at L-myc, Arg72Pro of p53 and Glu487Lys of ALDH2 as well as duplex genotyping for C-31T of IL-1B with VNTR of IL-1RN and A385T of secretor gene with se5, are demonstrated as examples with the primers and PCR conditions.