The 28-year-old Finnish defender completed his medical and was signed on Saturday morning by Schalke.
Uronen becomes the second Finn to represent die Knappen in the top flight after Teemu Pukki.
The defender said via a statement that he was looking forward to getting to know his new teammates and fans.
"Schalke 04 is very well known in Finland," Uronen said.
"I'm looking forward to getting to know my new teammates and especially to my first game in the Arena in front of the Schalke fans."
Schalke acting sporting director Peter Knabel, welcomed Uronen to the Bundesliga club, and said: "Thomas Ouwejan being in the final phase of his rehabilitation means we had to have a ready alternative at the [left-fullback] position.
"His [Uronen's] signing was a top priority," Knabel added.
Coach Thomas Reis was excited to now have two left-backs with different playing styles at Schalke.
"With Jere Uronen and Thomas Ouwejan, we now have two left-backs with different playing styles," Thomas Reis said.
"Jere is more defensively oriented and very disciplined in the back, while Thomas Ouwejan is stronger in attack.
"This flexibility will help us adapt to different opponents and playing systems," Reis added.
Schalke will next be in Bundesliga action on 10 January when they host 1. FC Nurnberg at Titanic Sports Centre.