The 63-year-old admits he is wary of how strong his side's rivals can become with an influx of arrivals and believes the Portuguese would be a "good solution" at Stamford Bridge
The Real Madrid boss has remained coy over his future with the Spanish club as he continues to be linked as the replacement for interim manager Rafa Benitez, who is set to leave Stamford Bridge when his contract expires at the end of the season.
Mourinho left Chelsea in September 2007 after his three-year reign produced two Premier League titles, one FA Cup and two League Cups, but Wenger believes club would be wise to give the 50-year-old a second spell in charge.
"I think Chelsea currently have a great coach in Rafa Benitez," Wenger told reporters.
"But if they part ways at the end of season, of course Jose Mourinho would be a good solution for Chelsea. Mourinho is one of the best in the world.
"I consider Benitez to be doing a good job at Stamford Bridge but, honestly, I'm not really well informed about the possibility of Mourinho returning to Chelsea."
Goal.com exclusively revealed in March that Chelsea will make Radamel Falcao the highest paid Premier League player if they secure the striker's services from Atletico Madrid this summer.
Chelsea have also been strongly tipped to land Bayer Leverkusen forward Andre Schurrle at the end of the season and Wenger concedes he is wary of how strong his side's rivals could potentially become with a wave of new signings.
"I'm afraid of what Chelsea can do in the summer," Wenger admitted.
"We have to be prepared for them to be one of the biggest movers in terms of investment once the window opens.
"Even though they already have a great base to their squad, notably their young players such as Oscar, Juan Mata, Ramires and Eden Hazard, I think they will be busy during the transfer window.
"We've heard a lot of talk about Falcao. Some people say it's already a done deal but I've heard nothing."