The Royal Danish Embassy in China announced the latest requirements for travelers on 4 November 2020 that said:
Attention! China is now tightening the entry rules to China. All foreign and Chinese citizens wishing to enter China must be able to show a negative antibody test from 7 November 2020 In addition, travelers must continue to show a negative Covid-19 test.
A negative antibody test must be presented to the Chinese embassy in Copenhagen 48 hours before the planned departure. The embassy will then issue a certified health certificate, a green health code that allows to enter China.
Please be aware that there will also be new requirements for antibody testing from transit destination.
You can find more information about the new Chinese entry rules on the Chinese embassy website: http://dk.china-embassy.org/eng/cs/t1828791.htm
If you have any questions, call the Chinese embassy in Copenhagen on their hotline: + 45 39460866