No details have been given so far as to the nature of the injury, but there are fears that the England international had suffered a broken metatarsal.
The 30-year-old picked up the injury in a challenge with Wolves midfielder Matt Jarvis and left Molineux with a protective boot on the damaged foot.
Brown is out of tomorrow's Champions League last-16 return leg against AC Milan, and will also miss Barclays Premier League games against Fulham, Liverpool, Bolton and a potential title-decider against Chelsea on April 3rd.