The Magpies have the option to make the move permanent, and the Algerian international will hope to impress on his return to the English top-flight.
Bentaleb, 25, spent three seasons at Tottenham Hotspur playing 66 games across all competitions before leaving for the Bundesliga in 2016.
The midfielder has featured in 97 games for Schalke, scoring 19 times, but didn’t play for them this term after falling out of favour with the manager due to disciplinary issues.
Bentaleb will hope to hit the ground running at Saint James’ Park and put the last six months behind him, and he has reacted on Twitter after joining Newcastle:
— Nabil Bentaleb (@nabilbentaleb42) January 21, 2020
Bentaleb brings much-needed depth to the Newcastle squad, but he faces stiff competition from the current crop of midfielders for playing minutes, and it will be interesting to see what he brings to the table going forward.