The stratigraphic and geochemical study of the Mesozoic mafic volcanic rocks of the Cordillera Oriental and Subandean belt of Bolivia shows that the emplacement of these volcanic intercalations took place during at least five episodes of intracontinental extension. Tholeiitic basalts (mid-Triassic), and alkali basalts and basaltic andesites (Jurassic, latest Jurassic-early Cretaceous, Barremian-Aptian, Coniacian) are distinguished. The extensional events evidenced by these volcanic episodes are in good agreement with the conclusions of previous sedimentologic and stratigraphic studies. There is an abridged English version. -English summary