"It's great to be married, the ceremony was beautiful and it was so special to be surrounded by our family and friends," the couple said in a statement released to People.
Sexy Back singer Timberlake, 31, and Total Recall actress Biel, 30, have been romantically linked since 2007. Timberlake proposed in December 2011, but details of the nuptials were closely guarded until the last minute.
They were spotted in Italy earlier this week, but have not revealed what day the ceremony went ahead. Reuters reports they threw a party for guests at the Borgo Egnazia resort near Bari, Italy.
Timberlake, who rose to fame in the boy band N'Sync, forged a successful solo music career before moving into film roles in The Social Network and Trouble With the Curve. He previously had relationships with pop singer Britney Spears and actress Cameron Diaz.
Biel began her screen career in TV series 7th Heaven and then moved into movie roles with Texas Chainsaw Massacre in 2003 and rom-com New Year's Eve and the Total Recall remake this year.