The aim of the present study is to reconstruct the depositional palaeoenvironment of the Almyros lignite seam cored at site #53, in Almyros Basin, Central Greece. Based on palynological and coal-petrographic data we obtained information concerning the coal-depositional environment, as well as the palaeoclimatic conditions in the surrounding area. At the above site, a peatland was developed in Upper Miocene - Lower Pliocene under limnotelmatic conditions. The climate was relatively wet and warm. Angiosperm herbaceous vegetation dominated in the fen, while Gymnosperms were sparse. The high content of detrohuminite suggests that peat was formed under reducing conditions, which favoured bacterial activity and humification of the organic matter.