The residents lit incense and laid flowers Monday at the statue of King Ly Thai To, a Vietnamese hero, and then marched around the landmark Hoan Kiem Lake, chanting "down with Communist China's aggression" in the commemoration that lasted an hour.
The 64 were killed in skirmishes with the Chinese at Johnson South Reef in the Spratly Islands and nine Vietnamese engineering soldiers were taken prisoner.
In the last two years China has reclaimed land conducted land around the Johnson South Reef to form artificial islands.