Deposition condition dependence of electrical and optical properties of B-doped (111) diamond films grown by the microwave plasma chemical vapor deposition (CVD) technique using a CH 4/H 2 gas mixture was investigated mainly by Hall effect and cathodoluminescence (CL) measurements. It was found that Hall mobility ( μ H) of hole and peak intensity due to free-exciton recombination (FE TO) and boron acceptor bound exciton recombination (BE TO) increased and the compensation ratio decreased as the CH 4/H 2 ratio (growth rate) increased from 0.05% to 0.25%, while the B incorporation efficiency was independent of the CH 4/H 2 ratio. These results are contrary to those of (100) diamond film growth and indicate that the growth and doping mechanisms of (111) diamond films are different from those of (100) diamond films. The difference in the doping mechanism between (111) and (100) is discussed.