The radioisotope 165 Er (T 1/2 =10.36h) is a candidate for Auger-electron therapy. The β − -emitting 166g Ho (T 1/2 =26.83h) is now being explored for various therapeutic applications. In the frame of our systematic study of charged particle production routes of therapeutic radionuclides the excitation functions of the 165 Ho(d,2n) 165 Er and 165 Ho(d,p) 166g Ho reactions were measured up to 20MeV by using a stacked foil irradiation technique and X/γ-ray spectroscopy. The excitation function of the 165 Ho(d,2n) 165 Er reaction was measured for the first time while for the 165 Ho(d,p) 166g Ho reaction only a single dataset of earlier measured cross-sections was found. The measured excitation functions were compared to the results of different nuclear reaction model codes. The calculated thick target yield of the 165 Ho(d,2n) reaction is significantly higher over the optimal energy range than that for the 165 Ho(p,n) reaction investigated earlier by us. The integral yield of the 165 Ho(d,p) 166g Ho reaction is rather low compared to the established 165 Ho(n,γ) 166 Ho reaction in a nuclear reactor.