The 22 year-old scored in the 5-1 Capital One cup win at Barnsley last week, but had not featured for the Saints in the Barclays Premier League.
Following the arrival of Dani Osvaldo, the Zambia international has been allowed to go out on loan to get some first-team games ahead of the World Cup.
Mayuka will stay at Sochaux until June 30, 2014.
Source: PA
Source: PA