Grain yield in barley is a complex character depending on a large number of environmental, agronomical and physiological characters. This research was carried out in Edirne (Turkey) region during 2015-2016 and 2016-2017 growing years. Experiment was set up with 22 cultivars in randomized completely blocks with four replications. Grain yields, plant height, days of heading, biomass, 1000-kernel weight, test weight and protein ratio and relationship among these characters were investigated. According to the results significant differences among genotypes were found based on studied characters. The mean yield was 652.7 kg da-1 and Sitara and Asparuh had the highest grain yield with 697.1 and 694.1 kg da-1, respectively. Analysis of the traits and genotypes showed varied correlations in the two growing environments. Grain yield was negatively correlated with days of heading (r= -0.549**), protein ratio (r= -0.575**), and plant height. Also, grain yield was positively correlated with peduncle length(r=0.549*), test weight (r=0.425*), and 1000-kernel weight. Protein ratio was positively correlated with days of heading (r=0.528**), and plant height (r=0.557**). There was negatively relationship between number of kernel in spike with protein ratio (r= -0.575**), and 1000-kernel weight (r= -0.617**). Generally, correlations between grain yield and investigated physiological parameters were low although a few were slightly significant. A negative correlation between grain yield and biomass constantly increased from GS25 up to GS40 growth stage. So, correlation coefficients between grain yield and biomass were at GS25 r=-0.300, at GS30 r=-0.300, and at GS49 r=-0.300*. This was probably because increased in rainfall and temperature between GS25 and GS49 and caused speed up the development of biotic stress factors which consequently resulted in reducing grain yield. Higher canopy temperature at GS55 and GS69 negatively affected and reduced grain yield. The chlorophyll content showed slightly positive correlations with yield. These results suggest that higher chlorophyll content during heading stage positively affected grain yield
