Marie Gustave Hector Ohier (5 August 1814 – 30 November 1870) was a French admiral who was Acting Governor of Cochinchina from 1868 to 1869.

He participated in the French blockade of the Río de la Plata and the capture of the fortified Martín García Island between Argentina and Uruguay.

He was promoted to capitaine de vaisseau (captain) in 1855 and commanded the Suffren, the gunners' training ship, and then the Toulon Division des Équipages.

On their recommendation Admiral Pierre-Paul de La Grandière, Governor of Cochinchina, made Hermitte head of his architectural department.

This ensured that if the French minister Léon Roches offered military aid to the Shōgun it would not have persuaded him to actively resist the emperor.

[6] Ohier was recalled from Japan to become Acting Governor of Cochinchina in place of La Grandière, who had fallen ill and had to return to France.

[3] When leaving Kobe the admiral gave orders for the Dupleix to survey the river on which Osaka stands and the coast as far as Sakai.

He signed the Treaty of the West Mekong on 25 August 1869, but was unable to persuade the emperor of Vietnam to confirm French rule over the three provinces they had seized.

[3] He was succeeded as acting governor of Cochinchina on 10 December 1869 by Joseph Faron, who held office until Alphonse de Cornulier-Lucinière arrived to assume the governorship.