Abstract. Abstract: Aim: This study evaluated and compared the changes in the Total Phosphorus (TP) and metals (Cd, Cu, Ni and Pb) contents and accumulation rates in the periphyton on different substrate types (PET and glass) in wet and dry periods in a shallow eutrophic reservoir. Thus, the potential of periphyton as a green biotechnology to remediate the eutrophication and promoting metal uptake were investigated. Methods: Floating substrate carriers made of wood (n = 3) containing glass and PET slides were submerged close to a sewage inflow site. Substrate exposure time was about 33 days in each period. Results: Periphyton TP and metal contents (Cu, Ni and Pb) were influenced by seasonality and the highest contents were found in the wet period. Periphyton metal contents were significantly different between glass or PET substrates, but no differences were detected in the TP contents. Conclusions: Seasonality was a determining factor for immobilization of TP and metals in periphyton. The highest potential of TP and metals immobilization by periphyton were detected in the wet period. Our results provided insights that the periphyton can contribute to remediate eutrophication and metal removal in aquatic ecosystems.