Subject of this bachelor thesis is comparison of non-commercial tools for UML modeling. The opening chapter is followed by brief description of the UML language in the second chapter. The fundamental mechanisms of the language and mainly the description of all the diagrams we are able to create by the help of UML are introduced here. Software development metodologies and their importance in the modeling process are also mentioned. Third chapter focuses on characteristics and classification of all CASE tools. General description of CASE tools is followed by the list of the best known UML modeling tools, both commercial and non-commercial. A description of four selected commercial products and their features is also added for illustration. Fu...