This paper is intended to determine the usefulness of duckweed (Lemna minor) and after treatment in stabilization ponds that treat domestic wastewater was analyzed a sample of water from wastewater effluent from the anaerobic lagoon treatment system Salguero wastewater the Valledupar-Cesar; the sample was inoculated with duckweed, which were taken from reservoirs located on the outskirts of the municipality in question. Assembly was performed using a batch type laboratory scale system with three replicates and two control parameters were analyzed nutrients (nitrogen and phosphorus). Nutrient removal was 72% and 95% N. P was established that duckweed have good efficiency regarding nutrient removal.