"Dope" co-star De'Aundre Bonds says he wasn't attacked in downtown L.A., and the gaping wound in his head was merely the result of taking a header ... all on his own.

As we reported ... Bonds was hospitalized last week when a friend found him unconscious. According to our sources, Bonds believed he'd been jumped by several attackers in DTLA, leaving him with a couple of nasty head injuries that required 10 stitches.

But when we got De'Aundre in Culver City on Monday ... he denied any attack. Listen to his version of events -- he's blaming diabetes and low blood sugar for the fall, and hints this kinda thing happens all the time.

As Bonds, who famously starred in "The Wood," puts it ... "I fall a little."