Awn is an important part of spikes in crops such as wheat and barley， and plays a crucial role in improving grain yield， seed dispersal， and resistance to pests. Several awn mutants have been reported in barley， and its diploid characteristics make it an ideal genetic model for the morphological formation of awns in Triticeae crops. This study reported the genetic mapping of the gene cal-d of barley calcaroides awn-type mutant. The mutant belonged to base-hooked awn with a hooked-like structure between the top of lemma and the base of awn， and displayed a reduction significantly in plant height， spike and awn length， grain number per spike， and the delayed heading date. Genetic segregation analysis revealed that the trait of cal-d was controlled by a recessive gene. Firstly， the cal-d gene was preliminarily mapped to chromosome 3H， using the cal-d introgression line derived from a cross between BW106 and Bowman to combine the F₂ population through genotyping by sequencing （GBS）. With genotyping a total of 13，000 F_2：3 plants derived from F₂ heterozygous plants to fine-map the gene， cal-d was delimited ultimately between 153-329 Mb， where the meager recombination rate was observed. Nine candidate genes were identified by transcriptome sequencing analysis in combination with the barley genome and expression profile resource database. Collectively， the results lay the foundation for the cloning and functional verification of the cal-d gene in barley mutant， and have important significance for analyzing the function of awn in Triticeae crops.