Road traffic accident analysis with actual open-source geoinformational systems such as OpenStreetMap, can make an improvement to a more accurate determination of exact spots, where accident actually occured and thereby traffic safety can be improved. In the theoretical part of this thesis, we presented basic operation functions of OpenStreetMap system, mainly focusing on the possibilities of editing and inserting data. The research methodology presents the operational principle of the traffic accident database and other relevant documentation such as police records. We have also compared standard police record with two in-depth accident research methods which are used abroad: the Finnish VALT and EU DaCoTA method. We analyzed three traffic accident locations listed in the Traffic Safety Agency database. Based on the findings, we described the relationships between the police record and the OpenStreetMap data using suggestions obtained from the VALT and DaCoTa methods. We have found that the OSM system offers many possibilities for entering a more accurate location of traffic accidents, as well as for census of the road surface and other circumstances of occurrence of the traffic accidents.