Starch gel electrophoresis has been used to study the polymorphism of hordeins encoded by the Hrd A, Hrd B, and Hrd F loci in 93 landrace specimens of barley assigned to 17 ancient provinces located in modem Turkey. Forty-five alleles of Hrd A with frequencies of 0.11-29.34%, 51 alleles of Hrd B with frequencies of 0.11-8.07%, and 5 alleles of Hrd F with frequencies of 0.75-41.29% have been detected. Cluster analysis of the matrix of allele frequencies has demonstrated that barley populations from different old provinces of Turkey are similar to one another. Cluster structure of local barley populations has been found, most populations (82%) falling into three clusters. The first cluster comprises barley populations from six provinces (Thracia, Bithynia, Pontus, Lydia, Cappadocia, and Armenia); the second cluster, populations from five provinces (Paphlagonia, Galatia, Lycaonia, Cilicia, and Mesopotamia); and the third one, populations from three provinces (Phrygia, Karia, and Lycia). Barley populations from Mysia, Pamphlya, and Syria do not fall in any cluster.