Trịnh Giang (chữ Hán: 鄭杠; 14 October 1711 – 30 December 1762) ruled northern Vietnam (Tonkin) from 1729 to 1740.

Also, a series of natural disasters struck, floods caused ruin for many villages and yet Trịnh Giang did nothing to relieve the suffering.

Instead, he obtained (through rich gifts) a new title from the Yongzheng Emperor of China, Supreme King of Annam (Vietnamese: An Nam Thuong Vuong).

This foolish action provoked a rash of revolts as the people felt he was usurping the title of the Lê Emperor.

As far as the Lê dynasty was concerned, the king, Hôn Đức Công (1729–1732), was imprisoned shortly after assuming the throne and was then murdered after three years.