Man of Two Worlds (1986) is a science fiction novel by American writers Brian and Frank Herbert.

All of the Universe is the creation of the Dreens, who possess the power of "idmaging", turning their thoughts into reality.

While the elder Dreens plan Earth's destruction, a youngster, Ryll, embarks on an unauthorized jaunt across space.

Forced for survival to merge bodies with an "Earther" whose mind is as strong as his own, he has to battle for control.

Dave Langford reviewed Man of Two Worlds for White Dwarf #80, and stated that "The combination of tension and daftness (eg, Dreens are helpless against the mind-rotting Earthly herb, basil) makes for an odd read.