The enhancement of the D-3He fusion yield by combined 3He beam injection and higher harmonic ICRF heating is investigated on the basis of the local Fokker-Planck calculation. With the fourth harmonic heating of 100 keV 3He beams the fusion yield is enhanced most efficiently when the ratio of the beam power to the radiofrequency power is 1/5. The maximum of the fusion power multiplication factor is roughly given by ΔQmax ∼ 0.043(Te[10 keV])(ne [1020 m−3])1.5. A comparison is made with the case of fundamental minority heating of 3He beams and the case of injection of 500 keV D beams.