Removal of nitrogen (N) and phosphorus (P) through biological treatment of wastewater is enforced in most developed countries to protect local waterways from eutrophication. Proper elimination of pollutants from effluents is essential in industrialized countries and is becoming increasingly important from an environmental and human health point of view in developing and emerging countries. Therefore, the removal of nitrogen and phosphorus compounds from wastewater is of vital significance. This paper reviews recent studies dealing with biological nitrogen and phosphorus removal technologies regarding their performance in removal efficiencies.