This paper reviews the trends in industrial and environmental biotechnology research in Tanzania for the past 20 years. Researches on production of bio-energy, enzymes and organic acids are reviewed. Furthermore, researches related to wastewater treatment systems including water stabilization ponds and constructed wetlands are covered. Brief highlights are made on researches related to bioprospecting and molecular biology techniques used in identification of organisms. In critically reviewing the research done so far, an attempt is made to pinpoint significant research gaps in areas such as single cell protein, biomining, biocomposting and bioengineering. This paper, therefore, provides an overview of the renewable raw materials available in the developing countries and outlines the researches that have been done to convert them to bio-products, while reducing bio-wastes. The identified gaps will serve as guidance to scientists who are interested in doing research in untapped areas of biotechnology.