We have focused on DNA strand exchange reaction (SER) with partially double-stranded (PDS) probes as a novel platform of SNPs genotyping. In this report, we elaborated the method for reliable and high-throughput SNPs typing. Competitive reactions using a couple of PDS probes designed for wild and mutant sequences significantly increase resolution efficiency to SNP types that is hardly discriminated by a non-competitive reaction with a single probe. Integration of the PDS probes with DNA microarray technology enable us to increase throughput efficacy. Simple and quick typing of fifteen SNPs with reliability as high as a ligase-based assay was demonstrated.