In the Czech Republic, Integrated Rescue System (IRS) is coordinated by regional emergency centres. Operators of these centres use the geographic information system for spatial analysis and visualization of the situation. It is obvious that the used cartographic visualization (colours, cartographic signs, etc.) should be unified in the whole Czech Republic to assure effective communication and organisation of emergency response – especially in a case of large disaster where IRS units from several regions need to be coordinated. The project “Geoinformatics as an instrument to support integrated emergency and rescue operations of state” aimed to develop a methodology of unified cartographic symbology for IRS. It consists of the recommended basic principles for the construction and definition of a symbol set, scaling range and standardized description of individual symbols to be used for maps in the analogue and digital forms. The presented paper describes the basics of the aforementioned methodology and experience retrieved during the IRS practice ZÓNA 2015, where the proposed cartographic visualization rules were used.