Objective To understand the change trends and its influencing factors of Zhang-Lu index (ZLI) among urban term newborns in China. Methods This study adopted a random cluster sampling strategy.Subjects were term singleton live newborns.Data were collected in four cities:Beijing,Harbin,Changsha and Guangzhou.Data were including all subjects' neonatal physical development conditions.Data analysis included comparison analysis and regression analysis.Comparison analysis was used to compare the study data with the national reference ZLI value.Regression analysis was used to identify ZLI influencing factors. Results A total of 5 140 subjects were included in this study (Beijing:n=1 207,Harbin:n=1 271,Changsha:n=1 250,and Guangzhou:n=1 412).In 2012,the value of term newborns (ranging 37 to 41 weeks' gestational age) of this study was higher than the national reference ZLI value collected between the years of 1989-1990.The ZLI values had statistically significant difference (P<0.01),and the average increasing mean value was 0.07.By multiple linear regression analysis,it indicated that main factors influencing the ZLI value were gestational age,maternal pre-pregnancy body mass index,gestational weight gain,maternal parity,age,education level,occupation,and neonatal gender. Conclusion The ZLI values of term newborns displays increasing trends among these studied four cities.In order to improve the quality of births,it should reduce the incidence of premature delivery,adjust pre-pregnancy body mass index in a appropriate level,appropriately regulate weight gain during pregnancy,and conduct pre-pregnancy and prenatal health education.