Visa required.
Visa Exemptions:
Nationals of China (People's Rep.) with a "Passport for Public Affairs" for a maximum stay of 90 days.
Nationals of China (People’s Rep.) with a normal passport arriving at Phu Quoc (PQC) for a maximum stay of 30 days.
Nationals of China (People’s Rep.) with a normal passport arriving at Hanoi (HAN) or Ho Chi Minh City (SGN) with a connecting flight to Phu Quoc (PQC) on the same calendar day. A maximum stay of 30 days will be granted for Phu Quoc (PQC).
Warning:
Visa exempt visitors not holding return/onward tickets could be refused entry.
Visitors with an e-visa or visa on arrival letter and not holding return/onward tickets could be refused entry.
以上是在IATA查到的信息,看起来只要有同一个日历日经河内或胡志明市转机起飞去富国岛也能免签