“The last two years at St Mirren were good for me,” he told Aberdeen’s website. “Scottish football is where I really made a name for myself and hopefully, I can pick up where I left off.”
Olusanya arrives as a replacement for Jesper Karlsson, who was recalled from his loan at Pittodrie by Bologna pending a permanent transfer to Utrecht.
Aberdeen have yet to replace the sacked Jimmy Thelin as manager, but sporting director Lutz Pfannenstiel believes they are making positive progress with three January signings.
“We’ve been clear that during this window we need to make changes to the dynamics of the squad,” he said.
“Toyosi’s arrival bolsters our attacking options and offers a different threat to what we currently have in the squad. He is physical and brings an aggression that we need at this moment.”
Overall, the forward scored 19 goals in 85 appearances for St Mirren.
Olusanya, who began his career with Wimbledon before spells with Kingstonian, Walton Casuals, Fleet Town, Gosport Borough, Cheshunt, Billericay Town, Middlesbrough and Arbroath, believes he is ready to face Livingston on Saturday.
