Abstract: In an attempt to assess the influence of egg shape index(transverse diameter/longitudinal diameter)on hatching effect of breeding eggs in Lhasa white chicken,the breeding eggs from 47-week-old Lhasa white chicken of the third generation were grouped based on the egg shape index and were hatched under the same condition.Furthermore,the correlation between egg shape index and hatching effect was analyzed.The results showed that when the index of egg shape ranged from 0.68 to 0.72,the highest value of 0 embryo age egg weight,average longitudinal diameter,the first candling inspection(at 11th day of embryo age)egg weight and second candling inspection(at 20th day of embryo age)egg weight were observed and were(51.92±5.27)g,(57.71±1.97)mm,(48.95±4.67)g and(45.47±3.97)g,respectively;when the index of egg shape ranged from 0.73 to 0.77,the highest value of hatching eggs hatchability,fertilized eggs hatchability and birth weight of chicks were observed and were 82.65%,86.60%and(36.31±4.71)g,respectively;when the index of egg shape ranged from 0.78 to 0.82,the highest value of the first candling inspection(at 11th day of embryo age)weightlessness,the first candling inspection(at 11th day of embryo age)weightlessness rate,the second candling inspection(at 20th day of embryo age)weightlessness,and the second candling inspection(at 20th day of embryo age)weightlessness rate were observed and were(3.35±0.93)g,(6.64±1.54)%,(6.70±1.47)g,and(13.47±2.56)%,respectively;when the index of egg shape ranged from 0.83 to 0.87,the highest value of average transverse diameter,fertility rate,healthy chick rate,and ratio of birth weight to hatching eggs weight were observed and were(42.82±1.23)mm,97.26%,95.96%,and(70.23±3.58)%,respectively;there was extremely significantly positive correlation between the birth weight of chicks and the ratio of birth weight of chicks to hatching eggs weight(P<0.01).This study provides a theoretical basis for the future selection of Lhasa white chicken.