Stringer suffered the injury during the fourth quarter of Friday night's one-point NAB Cup win over Hawthorn at Etihad Stadium.
It was Stringer's first senior appearance, and clouded a match where he came on as a substitute and kicked a goal with his first kick.
The Bulldogs sent the injury news out via their twitter account.
The Bulldogs play their round one match against the Brisbane Lions on March 30 – exactly four weeks away.
INJURY UPDATE: News in @jstringer9 scans show bone bruising and minor ligament damage of ankle. We'll see the pup back in 3-4 weeks.— Western Bulldogs (@westernbulldogs) March 2, 2013
Stringer was taken with the fifth pick of the 2011 National Draft after badly breaking his leg as a junior.
The ankle injury is on the opposite leg though.