Abstract Nigeria has vast figure of paper mills differing in size of operation and products found in most parts of the nation. This research involves the investigation of three samples of various pulps and paper mills in Nigeria. The various tests carried out include paper machine backwaters, physicochemical analysis of wastewaters produced by different processing and outlet to ETP (effluent treatment plant) for all the three mills analyzed. Some main parameters like, pH, color, oxygen demands and total solids were studied comparatively. Significant differences were detected between all the processing units of all three mills with p-values<0.02. This evaluation indicates that despite these mills have effluent treatment facilities available in their factories, upgradation are still required to improve their effectiveness for treating the effluents. Keywords: Waste streams, Pulp, Paper.