Târgu Trotuș (Hungarian: Tatros) is a commune in Bacău County, Western Moldavia, Romania.

It is composed of three villages: Târgu Trotuș, Tuta (Diószeg), and Viișoara (Viszóra).

At the 2021 census, the commune had a population of 5,330, an increase from the 2011 census, when the population was 4,969.

At the 2002 census, 99.9% of inhabitants were ethnic Romanians; 63.3% were Roman Catholic and 36.5% Romanian Orthodox.

This Bacău County location article is a stub.