The France Under 21 international came through the ranks at Nice and has been allowed to join St Mirren to build up first-team experience.
He is in contention to make his debut against Partick Thistle on Saturday and Buddies boss Danny Lennon is delighted to have added Bahoken to his squad.
"Stephane is a striker, 6ft 2ins, powerful and quick. He's made 22 appearances for Nice, got four goals," said Lennon. "He's the one we've been waiting for but I believe he's been worth the wait.
"We've been under no illusions that a striker is what we needed to give Stevie Thompson and Gary Harkins a hand up there. But we think we have identified the right one who will come in and give us exactly what we need.
"Esmael Goncalves who we had here last season was quite influential in telling Stephane about his experience here and how it helped his career. That was lovely of him to do.
Meanwhile, Lennon confirmed that transfer-listed defender Lee Mair is close to securing a move away from St Mirren.
Lennon added: "I did have a chat with Lee about a potential club showing an interest in him. That's as far as I know what is happening with that one. I have made the player aware of it.
"The most important thing is that Lee prepares himself properly and he has done. He's worked very well to make sure he's ready to go for his next challenge.
"Might he stay? You never know what will happen with your squad but it is an area that I'm well covered with Darren McGregor coming back in, while we also have Jason Naismith, a young lad coming through, so I'm well equipped. But if Lee is here, he will be a part of things."