The subject of this publication is to determine the impact of biogas plants on the environment, with particular emphasis on greenhouse gasses emissions associated with the production and management of biogas as the main plant product. The environmental impact of the agricultural sector as well as the state of development of the biogas market in European Union are presented as background for consideration of greenhouse gas emissions. One of the economy sectors responsible for GHG emissions is agriculture. One of the solutions of GHG reduction in agriculture is slurry management using biogas technology. It should be emphasized, that biogas not always has favorable emission parameters. The final emission throughout the whole life cycle of this energy carrier depends on many factors. The structure of GHG emissions largely depends on what type of raw material it used for biogas production and in what kind of tanks the digestate sludge is stored. If waste raw materials are used for biogas production, then GHG emission associated with their acquisition is assumed to be zero. On the other hand, if dedicated energy crops are used for biogas production, the emission connected with cultivation of these plants are added to the total GHG emissions. They are directly related to the use of fertilizers and plant protection products, field emissions of nitrous oxide and fuel combustion during the operation of agricultural machinery. Influence on the GHG emission has also the kind id digestate storage tank. If these are closed tanks, there is no emissions to the atmosphere. If tank is open, then methane is emitted directly to the air and is included in the total GHG balance.