A new tannin-based coagulant and flocculant agent has been tested on the removal of sodium dodecyl benzene sulfonate (SDBS), a dangerous and pollutant anionic surfactant. It is called Tanfloc and consists of a chemically modified tannin extract from Acacia mearnsii de Wild. Tanfloc has been revealed as an efficient product in anionic surfactant removal. Around 70% of SDBS removal has been achieved with Tanfloc doses of 150 mg.L-1. pH has a negative influence on surfactant removal, while the higher the initial surfactant concentration is the higher q capacity is obtained. Theoretical data adjustment has been carried out according to three different models: Frumkin-Fowler-Guggenheim (FFG), Gu and Zhu (G-Z), and Freundlich (F). Adjustment parameters have been obtained with r(2) levels above 0.90 in all cases.