Abstract: The objective of this study was to determine the relationship between heterosis and combining ability of beer barley， traits were measured in a complete diallel cross （Griffing П mating design） involving 21 hybrids and 7 parents during 2011-2012. The main results were as follows. there was great variation in the heterosis of height and its components， the average heterosis of internodes length was negative except for the first internode; the third and fourth internode had the larger average heterosis. Plant height and its components were controlled by both additive and dominant genetic effects， and the additive effect was the main factor. The general combining abilities of plant height and each internode length of Supi 3 and Gangpi 2 showed negative effect， and they could be used as parents in improving the structure of the plant height. The general combining ability of spike length of Lian 0719 showed positive effect， so it could be used as the parents in improving spike length. Except for the fifth internode, the specific combining ability of the other internode length in the three crosses involving Yangnongpi 5×Suyinmai 2, Gangpi 1×Supi 3， Suyinmai 2×Supi 3 showed negative effect， and the specific combining ability of spike length showed positive effect. They could be considered as the fine combinations in dwarfing breeding. The heritabilities of the plant height and its components were so high that these traits were suitable for early generation selection.

Key words: barley, plant height, heterosis, combining ability