Passport is a legal certificate issued by your country to testify your nationality and identity when you cross one country's frontier into another country.
You must have the passport with you all the time, the host country confirm your status according to your passport. If you have accident or you need help during the period of travel, passport is required.
If you lose your passport before you start your traveling, you need to report to security authorities and passport issuing office in your country immediately, and go to local newspaper to report the loss of your passport. If you lose the passport in China, you need to report to local public security organs and your embassy in China right away,
A passport with two opposing blank visa pages and validity of at least six-month is required for getting Chinese visa.