The 22-year-old, who was once the subject of a move from Leeds to Chelsea, agreed terms last week after leaving Carlisle at the end of last season. The switch to Easter Road was completed after clearance was received from the relevant footballing authorities.
Taiwo joins a Hibs side overhauled by manager Pat Fenlon and second in the SPL following a five-match unbeaten run. Taiwo told Hibs' official website: "The manager told me about his expectations and goals and how he wanted to improve me as a player."
He added: "Everything about this move seemed right and I'm looking forward to working hard, learning and putting everything I can into making the team successful.
"First of all, I'll be trying to establish myself in the team. The boys have started the season really well with some positive results and deserve to be second in the table.
"Then my next goal would be just to play as many games as possible for the club and to help Hibernian to qualify for the Europa League - every player wants to experience European football."