Hai Phong, Vietnam offers 1 beach perfect for sunbathing, surfing, swimming, and more. Hai Phong is known for Cat Ba Island and Do Son Beach. The best time to travel to Hai Phong, Vietnam, is from October to April, with average air temperatures around 20-25°C (68-77°F) and water temperatures approximately 23-27°C (73-81°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!