President Miguel Diaz-Canel tweeted, referring to the state-owned Cuban Petroleum Union.
Cuban state media said there were no reports of deaths.
“No casualties, injuries or fuel leakage into the sea after the fire were reported,” the Cuban Ministry of Energy and Mines wrote on Twitter.
An electrical discharge at the base of the oil tank, which stores crude oil, caused the fire to erupt, according to Susili Morva Gonzalez, first secretary of the Cuban Community Party in Matanzas province.
The ministry said the fire did not affect the Antonio Guitras Thermal Power Plant, which contributes to the national electricity system.
Gonzalez said provincial authorities, the fire department, the Revolutionary Armed Forces of Cuba and the Ministry of the Interior were battling the blazes.