The Portuguese forward was forced to undergo surgery after dislocating his shoulder during his side's Premier League defeat to Arsenal earlier this month
The 26-year-old, who has scored one goal so far this season, suffered the injury during the Hammers' Premier League defeat to Arsenal at Upton Park.
The Portuguese forward is now expected to begin rehabilitation, though his long-term absence is a blow to manager Sam Allardyce.
A statement from West Ham read: "West Ham United can confirm that Ricardo Vaz Te underwent successful shoulder surgery on Monday evening as he continues his recovery from the dislocation he suffered during the Barclays Premier League fixture against Arsenal on 6 October.
|UPTON PARK STALEMATE|
|12/1||West Ham are 12/1 with bet365 to draw 1-1 with Southampton|
"After being kept in hospital overnight for observation, Vaz Te will now start his rehabilitation, which is expected to take up to 12 weeks."