What are the qualifications to teach English in China?

Officially:

• 2 years' teaching experience (any kind of teaching, preferably teaching English as a Second/Foreign Language)
• TESL/TEFL/TESOL/whatever certification from any source
• A 4 year University degree from any university in any major

Unofficially (the reality):

• Native English speaker, preferably from the U.S., England, Canada, or Australia
• An Associate's Degree, but a 4 year degree is preferable and will help your job prospects

Basically, the "official" requirements are more of "preferences" from employers in China, and if you meet these requirements, it will be easier to not only find a job but get higher salaries as well.

It's simply a matter of supply and demand: the demand for native English speakers as teachers is far greater than the supply, so they do what they have to do in order to get teachers.

-T