Hely said that the players deserved the win as reward for the enthusiasm they showed, having been asked to attack instead of defend against Carlo Ancelotti's men.
"When you take on PSG, there are two options: to defend and counter-attack, or attack," Ligue1.com quotes Hely as saying.
"We chose the second option, and I'm happy the players were rewarded for their efforts. I think the difference was our enthusiasm and team spirit.
"It's our best performance of the season, both physically and technically. The win shows the progress we've made since the winter break and that we're on the right track."
The result lifted Sochaux to 14th in Ligue 1, three points clear of the relegation zone.