Three new Bolivian species of Euphorbia subg. Chamaesyce are described and illustrated. Euphorbia beckii is known from the Área Natural de Manejo Integrado of Apolobamba, province of Bautista Saavedra, department of La Paz; it belongs to sect. Alectoroctonum and is compared with E. viridis. Euphorbia fuentesii is known from the Kaa-Iya del Gran Chaco National Park, Cordillera province, department of Santa Cruz. It forms part of sect. Anisophyllum, and is most similar to E. catamarcensis. Euphorbia riinae is known from the Parque Nacional Noel Kempff Mercado, in the province of Velasco, department of Santa Cruz. It is a member of sect. Crossadenia subsect. Ephedropeplus and is closely related to the Brazilian Euphorbia gymnoclada.