Abstract: In order to analyse the heterosis of yield and traits of cotton， a set of recombinant inbred line （RIL） derived from a hybrid combination （sGK9708 × 0-153） was used to constructed an immortalized F2 （IF2） population. This IF2 population included 98 single crosses. The heterosis analysis of seven yield traits and their correlation of immortalized F2 population was studied. The results showed that this seven traits had obvious heterosis in different environments， middle parents advantage and advantage combination rate were both larger. In the correlation factors of production， boll weight was the greatest， followed by the boll number per plant and lint percentage. Permanent group competitive advantage was negative， so this immortalized F2 population could not be directly used theoretically in production， but it could be used as genetic group research materials.

Key words: cotton, immortalized F2 population, recombinant inbred lines, agronomic traits, heterosis