Lloris picked up the injury during Tottenham’s 3-0 league defeat by Brighton & Hove Albion on Saturday.
The 32-year-old Frenchman fell heavily into his goal as he tried to prevent Neal Maupay scoring after parrying the ball into the path of the Brighton striker.
He was treated for six minutes by medical staff on the pitch before being carried off on a stretcher while being given oxygen.
“The findings have shown that although surgery will not be required, our club captain has suffered ligament damage and is not expected to return to training before the end of 2019,” Spurs said in a statement.
“Hugo is currently in a brace and will now undergo a period of rest and rehabilitation under the supervision of our medical staff at Hotspur Way.”