Mouyokolo passed a medical on Wednesday morning before agreeing a deal that Sochaux can make permanent at the end of the season.
"The FCSM has registered their second arrival with the loan of Wolverhampton Wanderers central defender Steven Mouyokolo," a statement on the club's website.
"He will be officially presented on Wednesday afternoon.
"Mouyokolo committed to the club this morning after a meeting and successfully completing his medical.
"The central defender, 24, is on loan with option to buy."
Mouyokolo moved to Molineux from Hull last summer but his first-team opportunities were severely limited.
He will now return to France, where his impressive form during short spells at Gueugnon and Boulogne saw him signed by then-Hull boss Phil Brown in 2009.
The Congolese-born Frenchman becomes Sochaux's second summer signing after the club completed a deal to sign midfielder Sebastien Roudet from Lens.
Source: Team Talk
Source: Team Talk