Metta World Peace Joins Comedy Boot Camp -- I'm SERIOUS About Stand-Up

Metta World Peace is taking his aspiring comedy career VERY seriously -- and TMZ has learned he's even enrolled in a stand-up "boot camp" to hone his skills during the NBA lockout.

MWP made his comedy debut a few months ago ... and has another big show scheduled at the Planet Hollywood in Vegas later this month.

But sources close to the basketball star tell us he is dedicated to making improvements -- and has joined the "Laff Mobb " comedy group in L.A. ... which claims its worked with HUGE comics in the past, like Bernie Mac, Chris Tucker and even Dave Chappelle.