Wine developer Chris Murphy will be moved across to head up the project.
M&S wine buyer Jo Ahearne said: "We didn't have a very robust platform before, but now it will be much better suited to buying wine."
Currently the online shop - www.marksandspencer.com - offers single bottles, mixed cases, wine accessories and glassware.
The retailer has also confirmed that its former head of wine, Jane Masters MW, is returning to work for the beers, wines and spirits team.
Masters, who headed up the team for 11 years and achieved her Master of Wine status in 1997, stepped down from the role in 2003 following an internal promotion.
During her tenure she was one of the trade's most influential buyers and among the most highly-ranking women in the UK off-trade.
She will now work for the wine team as a consultant.