The aim of this work is to evaluate the nutritional value and cyanhydric acid content of eight plant species (Alchornea cordifolia, Alstonia boonei, Cola acuminata, Ficus vallis-choudae, Musanga cecropioïdes, Macaranga spinosa, Pycnanthus angolensis and Trilepisium madagascariensis) currently consumed by Okapia johnstoni in captivity at Epulu Fauna Reserve of Okapi in Democratic Republic of Congo. After two weeks of experimentation, the preference of Okapia johnstoni in consuming these plant species is in decreasing order as follow: Musanga cecropioïdes, Alchornea cordifolia, Alstonia boonei, Ficus vallis-choudae, Pycnanthus angolensis, Trilepisium madagascariensis, Macaranga spinosa and Cola acuminata. The biochemical analyses revealed that A. Boonei and C. acuminata are more rich in crude protein( 19.27% per 100 g of dry mater) and F. vallis-choudae is the richest species in the lipids (11.61%) and the poorest is A. cordifolia; M. cecropioïdes is the richest in calcium (6. 01%) against, P. angolensis which is the poorest (3.0 %); In the all plant species, magnesium is presented under the form of the trace; T. madagascariens and A. Boonei are the richest in cyanhydric acid (1, 60 mg) that P. angolensis (0, 40 mg). These results indicate that the selective choice of certain fodder to the detriment of others is a self medicative behaviour (zoopharmacognosy) in Okapi. Starting from these results, it is thus desirable that research works are carried out for the ex situ conservation of Okapi in the province of “Nord Ubangi”.