The euro zone crisis will seriously politically influence the development of integration in the whole European Union. In case of lack of proper response to the euro zone crisis there will take place diversified integration in the whole European Union which, assuming the most likely scenario, will initiate Europe of the so called “two speeds”, that is the very center comprising the states of euro zone on one hand, and its peripheral states connected with the center by means of their inner market on the other hand. The results of the diversified integration would take politically – institutional shape and might display federalization of euro zone and leaving the current institutional structure for the whole European Union. The crisis of the euro zone reveals weakness of the Lisbon Treaty solutions against their fervent supporters’ opinions concerning this amendment. In other words, The Lisbon Treaty did not save Europe against the crisis due to the fact that a reform of an institution without demonstrating political will of its state members does not mean much. The crisis of the euro zone proves the weakness of foundations on which The European Union is based. Also, it is an example of both a leadership crisis of its member states and the crisis of the whole European Union as well, which leads to the problem of legitimization. Summing up, the following issues have been analyzed in the article: the notion of crises in the EU (including their reasons), political consequences of most important crises of the fifties in the twentieth century, concepts and possibilities of the diversified integration as part of the European Union, possible scenarios and political consequences of the crisis for European integration in the euro zone.