1.Ask the original employer to cancel the work permit that is still valid.
2. The original employer issue a letter, with which go to the local entry and exit administration to apply for cancellation of the work residence permit that is now valid (the letter may include: indicating that the work permit has been canceled, and now applying for cancellation of the work residence permit, and as the person will still work in China, ask the local entry and exit administration to issue a stay visa for him to apply for a new work permit).
3. At the same time, prepare the documents and materials for applying for a new work permit.
4. The tips mainly refer to the change of work & place by foreigners who have a valid work permit in China. If foreigners in China do not have a work permit and a residence permit for work, articles 1 and 2 maybe ignored.