By what means can the Immigration Bureau check whether a person has a nationality?

If you are a foreigner in China, you should mainly check your ID card and household registration information.

If China people immigrate and naturalize in other countries, because the validity period of China passport is 10 years, it will be exposed when it expires. Moreover, the household registration system and embassies abroad have networking systems. China border inspection will also check the exit visa at the time of entry and exit.