This thesis is an overview of available technological processes for landfill leachate treatment. The emphasis is on the best available technologies, which are most commonly used in the Slovenian area. Landfills are divided into three groups based on their operational status. Operational landfills, landfills currently in closing process and closed landfills, which had monitored data of landfill leachate for at least 5 year long period were chosen. According to the obtained data, conclusions and proposals on existing landfill leachate treatment management were given. As a case study of good management practice, CERO Špaja dolina is discussed. They are trying to change their existing leachate treatment process with economically more appropriate one. For this purpose an economic comparison of the available options was made.