This paper is concerned with analyzing the trends of sex mortality differentials in China since the
1980s and contributions to the sex differentials in life expectancy at birth due to the gender
differentials in age-specific mortality rates, and compares such kinds of contributions of
cause-of-death under decomposition method using the data of censuses and surveys from 1982 to
2000, and of China Health Annals (CHA) in 1989, 1995 and 2000 respectively from
Cause-of-death Registration System of China Health Ministry (CDRS). In the past two decades in
China, the gap of life expectancy at birth between female and male had been continuing to be
widened. Major reasons were of the contributions of sex differences in age-specific mortality rates
and their changes, particularly for the population aged 45 years old and above, for the population
aged 45 years old and lower, the contributions, however, had been increasing significantly. We
also examine cause-of-death contributions to the sex gap of life expectancy at birth with broad age
categories between 1989 and 2000, and find that sex disparities in mortality rates due to malignant
neoplasms, circulatory diseases and accidents and injuries account for most of the total sex
differences, and represent their individual characters in age groups. In the past decade, sex
differences due to circulatory diseases, accidents and injuries increased dramatically, and kept
steadily due to malignant neoplasms.