A 6-foot-9 sophomore, Obekpa led Division I in 2012-13 with 4.03 blocks per game and he led the conference this season with 2.9 blocks per game.
Red Storm head coach Steve Lavin announced the release Thursday, adding that guard Max Hooper, who graduates from St. John's in May, has been granted permission to pursue postgraduate studies elsewhere.
Obekpa's 133 blocks as a freshmen are St. John's season record. He finished his two years with a school-record 227 blocks. Obekpa averaged 3.9 points and 5.5 rebounds for his two seasons.
Hooper, who transferred from Harvard after his freshman season in 2011-12, averaged 3.2 points this season.