The front row prospect, who turns 22 next month, previously had playing spells at US Carcassonne in the Pro D2 and was at Dijon in Federale 1 before being given his chance in the Top 14.
Bécasseau becomes the second player to join Warriors from Stade Francais this summer after Paul Warwick agreed a move earlier this year.
Director of Rugby Dean Ryan said: "Jeremy is a driven and ambitious young man who is coming over from France to a new environment determined to make an impression.
"His path forward has been blocked at Stade Francais by a number of high profile signings and so he is taking this opportunity to really push himself. I like his attitude and the ambition he is showing, he is stepping out of his comfort zone because he wants to succeed.
"We were alerted to his availability and, in the context of the current injury we have to George Porter ahead of next season, we are pleased to have secured someone of his abilities at such short notice."
Bécasseau said: "I am very happy to join Worcester Warriors. It is a new challenge and I am looking forward to joining the team and starting training.
"It's a big move for me to come into the Aviva Premiership, but I am definitely excited about representing the Warriors.
"I was very happy when I came over to visit the club with the set-up, the structures in place and facilities. I now look forward to training hard and the start of a new season."