A review has been made of the ethnobotanical and pharmacological data of 43 medicinal plants of the tree-savannah used by the Diola against infectious diseases. The traditional use of ten plants can be explained by pharmacologically active principles: Adansonia digitata, Azadirachta indica, Carica papaya, Cassia tora, Fagara leprieurii, Guiera senegalensis, Khaya senegalensis, Mangifera indica, Psidium guajava and Voacanga africana. Four of these herbs are recommended for use in Primary Health Care. The therapeutic value of the other plants discussed is not absolutely clear. It is, however, obvious that herbal medicine has a large potential, which is still insufficiently explored, for utilization in Primary Health Care.