The French oil firm said its Chinese counterpart was paying $2.5bn (£1.6bn) for the stake in the OML 138 oil block.
The block includes the Usan oilfield, which began producing in February, and is jointly owned with Chevron, Exxon and Canada’s Nexen.
Total said in September it aimed to sell $15bn-$20bn in oil assets by 2014 to raise cash for new projects.
The sale, which will be paid for in cash, still needs to be approved by the Nigerian authorities.
The Nigerian state oil company, NNPC, holds the concession on the oilfield.