Sacha inchi (Plukenetia volubilis) is an oilseed crop that has gained importance due to the high contents of proteins and unsaturated fatty acids in its seeds. This study aimed at evaluating the growth characteristics of five leguminous species (Crotalaria juncea, Centrosema macrocarpum, Arachis pintoi, Cannavalia ensiformis and Phaseolus vulgaris) used as cover crops, as well as determining their influence on the sacha inchi yield. A complete randomized block design, with three blocks, was used. C. macrocarpum and C. ensiformis were the most appropriate cover crop species for the local edaphoclimatic conditions because they reached 100% of soil coverage at six months, in addition to controlling the weeds growth and protecting the soil from erosion. Furthermore, the total leaf biomass at six months was significantly higher in C. macrocarpum, what allowed improving the soil fertility through nitrogen cycling. The use of leguminous cover crops, mainly C. macrocarpum, positively influenced the sacha inchi yield.