概念上一个是 返回值 一个是打印输出
区别一：return是结束语一般放在函数的最后，当你在return 结束后面再写一些东西是不执行的如 下
def renshu(x,y):
h=x+y
print (h)
return h
print (‘hello word‘)
print (renshu(3,7))
执行后的结果是 Hello word 不执行。没有报错
C:\Python34\python.exe C:/Users/Administrator/PycharmProjects/python/class/suibi.py
10
10
1 C:\Python34\python.exe C:/Users/Administrator/PycharmProjects/python/class/suibi.py 2 10 3 10
def renshu(x,y):
h=x+y
print (h)
return h
print (‘hello word‘)
print (renshu(3,7))
x= (renshu(3,7))+10
print (x)
执行结果是
C:\Python34\python.exe C:/Users/Administrator/PycharmProjects/python/class/suibi.py
10
10
10
20
Process finished with exit code 0
print 仅仅只是打印没有结果 
def renshu(x,y):
h=x+y
print (h)
print (renshu(3,7))
x= (renshu(3,7))+10
print (x)
报错信息
None
File "C:/Users/Administrator/PycharmProjects/python/class/suibi.py", line 13, in <module>
10
x= (renshu(3,7))+10
TypeError: unsupported operand type(s) for +: ‘NoneType‘ and ‘int‘
Process finished with exit code 1
原文：http://www.cnblogs.com/yubenliu/p/5516781.html