Humic substances (HS) constitute a large part of organic matter found in aquatic environment. The HS strongly interact with both inorganic and organic pollutants. Occurrence of the HS in groundwater accounts for many problems with treatment procedures. These natural components cause an increased intensity of water colour, affect its taste and odour, hinder removal of iron, manganese and other metals, organic substances such as, e.g. pesticides from water. The HS are precursors of toxic trihalomethanes during chlorination. For treating groundwater contaminated with humic substances and iron compounds it is not enough to apply solely a conventional groundwater treatment system. Therefore, searching for new methods of removing humic substances from groundwater is a common practice and the existing methods undergo regular improvement. This paper, based on the review of published materials, deals with problems related to the existence of humic substances in groundwater and further discusses possibilities of their removal in order to obtain water that would meet requirements of water intended for human consumption.