The Hammers will reportedly have funds to spend in the next transfer window, as they look to add even further quality to a squad which has performed above expectations this season.
West Ham are currently challenging for European football, and they are just one point behind the top four.
With West Ham set to move to the Olympic Stadium next season, they are already drawing up ambitious plans, and Mendy is reportedly on their wishlist.
West Ham had great success recruiting with Dimitri Payet last summer, with the French international already becoming a fans favourite at Upton Park and they are hoping to repeat the trick with Mendy.
The 21-year-old left-back has played 27 times for Marseille in all competitions this season, scoring once and claiming five assists.
If Mendy was to move to West Ham, it would be unlikely that he would go straight into Slaven Bilic's side's first XI, but he would provide competition for Aaron Cresswell.