The 21-year-old played 13 times for Spurs last season in an injury-plagued campaign.
"Bentaleb is 100 percent fit, but we need to be patient and give him a little time to integrate into the team," Schalke director of sport Christian Heidel told reporters.
Although no financial details were released, local media reported that Schalke have the option to make the deal permanent for 15 million pounds at the end of the season.
Schalke, who finished fifth in the Bundesliga last season, face Eintracht Frankfurt in their opening game of the new campaign on Saturday.
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(Reporting by Shravanth Vijayakumar in Bengaluru, editing by Ed Osmond)
