【摘要】A enterprise is also a life to some degree,and has its own age.The first economic census indicates that most of the under designed-size enterprises are rather young,their average age is 6 years old.The enterprises' average age in the east is younger than in the central and west of China.The private enterprises' average age is relatively younger than other ownership enterprises.Enterprise's age has a positive correlation with its payroll and assets' size.The younger enterprise is more efficient than the old.