The calculated distance (air line) between Ho Chi Minh City and Phu Quoc is approximately 185 miles respectively 298 kilometers.
By car or train, the actual journey to Phu Quoc is certainly longer, as only the direct route (as the crow flies) between Ho Chi Minh City and Phu Quoc has been calculated here.
Air line (approximately)
298 kilometers
161 nautical miles