Abstract: The present study was conducted by using laying ducks of 6 lines from 2 native breeds in Zhejiang and 50 eggs of each line. Each egg was measured for egg shape index， shell thickness， shell strength， egg specific gravity， albumen height， Hough unit， yolk weight and yolk percentage. Moreover， multiple comparisons for egg quality traits were conducted in different breeds and lines and their heretability were estimated. The results showed that eggshell quality in Shaoxing duck was significantly higher than that of Jinyun duck， while， albumen and yolk quality of Jinyun duck were superior to Shaoxing duck; the comparison among different lines showed that eggshell quality were the highest in Shaobai line and blue shell line of Shaoxing duck， quality of albumen and yolk among 3 strains of Jinyun duck existed only little difference; the results of estimation of heretability for egg quality traits revealed that egg specific gravity and shell thickness had the highest heritability values(0.72 and 0.47， respectively）， and the heritability of Hough unit was the lowest（0.06）. Our finding suggested that egg specific gravity and shell thickness could be improved by genetic breeding， while albumen height， Hough unit and yolk percentage might be promoted through environmental control.

Key words: duck, egg quality, heritability