Objective To analyze the gender difference of life expectancy in urban people of China and to explore both age-specific and cause-specific contributions to the changing differences in life expectancy on genders.Methods Data on life expectancy (male and female) and mortality were obtained from the "Annual Statistics of public health in China".Male-female gender difference was analyzed by decomposition methodologies,including age-specific decomposition and the causespecific decomposition.Results Women had lived much longer than men in the Chinese urban citizens,with remarkable gains in life expectancy since 2005.Difference in gender reached a peak in 2007,with the gap of 5.3 years.Differences on mortality between men and women in the 60-79 age groups made the largest contribution (42％-47％) to the gap of 6 years on life expectancy in genders.With the widening of the gaps in gender on life expectancy between 2005 and 2007,faster declining of mortality among groups of women in age 0-1 age and over 75 years old groups made the largest contributions.Between 2007 and 2008,along with the reduction of gaps in gender,all the age groups except the 1-15 and 50-55 year-olds showed negative efforts.In 2009-2010,the widening gaps in gender on life expectancy were caused by the positive effect in the 60-70 age group.Among all the causes of death,cancer (1.638-2.019 years),circulatory diseases (1.271-1.606 years),respiratory diseases (0.551-0.800 years) made the largest contributions to the gender gap.33％-38％ of the gaps in gender were caused by cancer and among all the cancers,among which lung cancer contributed 0.6 years to the overall gap.Contribution of cancers to the gender gap was reducing,but when time went on it was mostly influenced by the narrowing effect caused by liver cancer on the gap in gender.Traffic accidents and suicidal issues were the external causes that influencing the gender gap and contributing 10.60％-15.78％ to the overall differentials.Conclusion Public health efforts in reducing the excess mortalities for cancer,circulatory and respiratory diseases,suicide,among men in particular,will further narrow the gender gap on life expectancy in the urban cities of China.