Water is the natural element that is found in greater quantity on the planet, which is responsible for the prosperity of the different forms of life on earth. One of the main problems that humanity is going through, with respect to this element, is that every day it becomes a limited resource, largely due to the contamination of the different natural water sources and the generation of wastewater, whether industrial or domestic. Developing sustainable and environmental-friendly technologies is the challenge of modern society. So that these remediation technologies generate in turn the least possible impact in the remediation of these waters. These new technologies focus on the use of microorganisms, specifically in the versatility of adaptation and metabolism that they possess. What emerges as a new vision, known today as bioremediation, considered as a biological tool in the treatment of wastewater, which promotes the emergence of new biotechnologies. Between the most outstanding is the use of microalgae, microorganisms with a great adaptation to different substrates from organic matter to waters contaminated with heavy metals.