Having starred for Celtic during his two-and-a-half years in Glasgow, Ntcham is naturally attracting interest from the Premier League.
According to The Sun, the Saints have identified the 23-year-old as a potential addition as Ralph Hasenhuttl looks to strengthen his squad.
The report suggests that Ntcham is regarded as a possible replacement for Pierre-Emile Hojbjerg, who has less than 18 months left on his contract.
Celtic are likely to demand a sizeable fee for the Frenchman, potentially quadrupling the £4.5m which they paid Manchester City in 2017.
Ntcham has scored 21 goals from 116 appearances in all competitions.