Wo men you mei you gui ding han zi zi xing de biao zhun?
(Do we have a standard to define the form of Chinese Character?)

There are many standards related with Chinese character(see this:
http://www.china-language.gov.cn/wenziguifan/index.htm).

And they have been issued and updated by the goverment through the years.Nowdays, the form of the character currently bases on the stardard:”Modern Chinese Character Set for Universal Use “(现代汉语通用字表) ,which issued on March 25,1988 by two department :State Language Commission,and Press and Publications Administration of China(国家语言文字工作委员会，中华人民共和国新闻出版署).