The show, which is spearheaded by former Stargate:SG1 actress Amanda Tapping, drew an impressive three million viewers for its first season premiere.
Sanctuary has been heralded as breaking new ground in television as it is almost entirely shot against a greenscreen with the backgrounds added later by digital technology.
Mark Stern, the Sci Fi Channel's executive vice president of original programming, heralded the decision to renew the series, which began life online.
"Sci Fi will continue to trail-blaze the television landscape by further exploring the many worlds of Sanctuary through its unique green-screen environments," he said.
"Technology and great storytelling makes Sanctuary a fantastic addition to Sci Fi's 2009 lineup."