Before Hungary joined the European Union on 1 May 2004 the Hungarian Standards Institution had become the full member of the European Committee for Electrotechnical Standardization (CENELEC) on 1 June 2002. Thus, within a given interval our country had to replace the then existing national standards with those being in effect in the whole community and withdrew all that had been in clash with the new standards. The change had an impact on the standard concerning lightning protection regulations. Until 1 February 2009, both the old MSZ 274 standard and the regulatory EU standard MSZ EN 62305 were in effect. However, after 1 February 2009 the MSZ 274 standard was lapsed and from that time forth lightning protection systems must be planned in accordance with the 9/2008. (II.22.) ÖTM regulation, which is built on the old standard in essence. Respectively, supervisors can qualify lightning protection systems correct, if they are in accordance with this standard. In the course of my thesis I planned the lightning protection system of a dwelling house according to the old and the new standards. The dwelling house consists of 18 flats and was built in my hometown, Nagykáta. The promulgation of the new standard hit many engineers unprepared. It exceeds greatly the quantity of the former standard and since it is totally different in its approach from the former one it will be hard to get used to it for those professionals who have been doing their jobs for decades in accordance with a conventional and clear-cut standard. Concerning execution, the new standard gives far more freedom to the planners, nevertheless, it puts more responsibility on them. In my thesis I try to summarize the differences between the old and the new standard.