We performed a genome-wide association study with 23,465 microsatellite markers to identify genes related to adult height. Selective genotyping was applied to extremely tall and extremely short individuals from the Khalkh-Mongolian population. Two loci, 8q21.13 and 15q22.33, which showed the strongest association with microsatellites were subjected to further analyses of SNPs in 782 tall and 773 short individuals. The most significant association was observed with SNP rs2220456 at 8q21.13 (P = 0.000016). In the LD block at 15q22.32, SNP rs8038652 located in intron 1 of IQCH was strongly associated (P = 0.0003), especially the AA genotype of the SNP under a recessive model was strongly associated with adult height (P = 0.000046).