Abstract: Tannery Liquid effluents collected from the Challawa Industrial Estate in Kano City were treated with aqueous extract of Moringa oleifera Lam seeds whereby 20gms of the seed powder was extracted with 250cm3 of distilled water. Then 20cm3 of the aqueous extract was used in the treatment of 100cm3 of the effluent as the extract volume was found to be the optimum level that would provide the best treated effluent water quality. Some physicochemical and biochemical parameters of the treated effluent were measured using standard analytical techniques. When the results were compared with effluent samples treated with alum, remarkable improvement in the water quality was observed in favour of the samples treated with the plant extract. For instance, improved turbidity values on samples obtained from the production lines in one of the tanneries and other areas within the estate ranged between 54% and 79% above what was obtained using alum. The aqueous extract of Moringa oleifera was very effective in the removal of the solid matter in which 100 per cent effectiveness were obtained for the total, dissolved as well as suspended solids. The advantage of using the aqueous extract of the Moringa oleifera seed powder is the wide dose range over which effective treatment can be achieved and maintained without affecting the recycled water quality.