Dorukhan Tokoz's through ball met with Cengiz Under, as his powerful shot from the right cross beat Hugo Lloris.
"That was a slap in the face for us and there's not a lot I can say", Deschamps told French broadcaster TF1.
The highly rated 21-year-old Under, who has caught the eye several times with Roma in Serie A, put Turkey further ahead 10 minutes later with a fine finish.
Former Turkish goalkeeper Gunes took the reins of the national team for a second time to pick up a side mired in a slump that saw them fail to qualify for last year's World Cup in Russian Federation.
"Nothing more to add apart from to say well done to Turkey, and to get back to basics".
France will look to bounce back from this disappointing result while Turkey will attempt to make it four wins from four in Euro 2020 qualifying when they face Iceland.
Turkey's players celebrate winning the UEFA Euro 2020 qualifier Group H soccer match between Turkey and France in Konya, Turkey, on June 8, 2019.
"When you have a performance like that, there are no positives to take", the France coach was quoted as saying by L'Equipe.
"We didn't put in the match we needed to against a team that played their game. That's top-level football and it's the same whether you are world champions or not".
Turkey lead Group H with nine points, having won all three games so far.
In other matches, Germany defeated Belarus 2-0, Italy defeated Greece 3-0, Scotland defeated Cyprus 2-1 while Iceland defeated Albania 1-0. "Overall, we did it well", said Germany assistant coach Marcus Sorg, who is also to be in charge in tomorrow's qualifier against Estonia.
Roberto Mancini's side are in pole position after picking up three wins from their opening three games without conceding a goal.
Les Blues were pegged back on the half-hour mark when Kaan Ayhan turned home a cut- back from the right with a thumping header.
Finland moved into second place on six points with a 2-0 win over Bosnia in Tampere.