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A striking feature of Triticum carthlicum Nevski (2n = 4x = 28, AABB genome) is an awn-like appendage on the glume, so all the spikelets appear four-awned. From the word “tetraaristatus” (four-awned), the locus was named “t” to distinguish it from the b 1 locus on chromosome 5A and b2 locus on chromosome 6B for awn formation. The aims of present study was to determine the chromosomal location of the t locus in tetraploid wheat T. carthlicum, and (2) to assess linkage relationships of t, Rht12 using microsatellite markers in T. carthlicum. Combined cytological evidence and microsatellite mapping showed that t was located on the chromosome 5AL. The alignment of the gene was Xgwm291–(6.4 cM)–t–(6.7 cM)–Xgwm410 in F2 of T. carthlicum #521/LD222, and Xhbg219–(12.4 cM)–t–(5.1 cM)–Xgwm410–(6.2 cM) –Rht12 in F2 of ANW 16C/#521 on the 5AL. The t locus was different from b1 locus, because it was known that the semi-dwarf Rht12 gene was completely linked with b1 gene. We discussed that the four-awned phenotype of T. carthlicum was introduced from Triticum aestivum L. ssp. carthlicoides.