The objective of the paper is to determine the influence of continentality of Europe's climate, increasing to the east, on the number of days with thunderstorms during the years 1994-2005 in ten chosen European cities. In Europe, days with thunderstorms come from cities located in zones from the west to the east, beginning from Dublin, through London, Paris, Munich, Prague, Minsk, Kiev, Kharkov and up to Moscow. The well matched stations show the gradually increasing continentality of Europe's climate. From an analysis of the number of days with thunderstorms, the Gorczyński continentality index and the long-term mean annual amplitude of air temperature it may be concluded that, in as much as the values of the amplitude and index increase with distance from the ocean, it is not always so with the number of days with thunderstorms. Despite greater climate continentality, Minsk, Kiev and Moscow have much fewer storm days than Warsaw or Prague.