In the Lusitanian Basin (west-central Portugal), Upper Jurassic (Oxfordian) sediments were investigated in order to identify palaeontological assemblages of charophytes. Systematic studies were undertaken on specimens obtained from four field sections (Pedrógão, Vale de Ventos, Memória and Valverde). These studies revealed the presence of new forms of <i>Porocharaceae</i> (<i>Porochara pedunculata</i> n. sp) and of forms previously unknown in this region (<i>Auerbachichara</i> cf. <i>saidakovskyi</i>), as well as <i>P. raskyae</i>, <i>P. minima</i>, <i>P. fusca</i>, <i>P. sulcata</i>, <i>P. kimmeridgensis</i>, <i>Aclistochara longiformis</i> and <i>Porochara</i> sp. Comparison of the charophyte palaeofloras recognized in all of the studied sections has allowed the definition of three different assemblages which, coupled with other data, help to correlate these successions of Early (?) to Middle (Late?) Oxfordian age.