Treasury spokesman Steve Adamske said Geithner began experiencing pain from a kidney stone Thursday night and was admitted to a Washington hospital Friday morning.
Adamske said that Geithner will have what he called a "minor surgical procedure" performed Friday afternoon and expects to be back at work on Monday.
The illness did force Geithner to cancel his Sunday appearances on three television network news programs where he had been scheduled to promote the tax-cut deal that the administration reached with congressional Republicans this week.
Adamske said that when Geithner was asked Friday morning how much pain he was in, Geithner replied, "As between this and doing the Sunday shows, it's a close call."
Treasury did not immediately supply details of what type of procedure Geithner will undergo, but typically kidney stones are dealt with by using either sound waves to dissolve the stone or minimally invasive surgery via a catheter.