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In accordance to PNAE G-7-008-89 [1] on the NPP since starting-up should be accounted neutron fluence of RPV, which determines the RPV life-time in accordance to strength calculations. Detailization of these PNAE G-7-008-89 [1] requirements has been represented in the RB-007-99 [2]. Recently elaborated procedure for accounting and prediction of RPV fast neutron fluence has been regulated by normative document RD EO 1.1.2.29.0913-2012 [3]. During NPP unit operation some modernizations have been realized, for example, using of new types of fuel assemblies and new kind of fuel. Changes in the reactor core loading, especially on the core periphery, give influence in the fast neutron fluence on the RPV, which should be evaluated by neutron fluence calculations. The reliability of these calculations should be validated by ex-vessel neutron-activation measurements at NPPs with VVER. Paper deals with the results of calculations and measurement of fast neutron fluence on the RPV for last fuel cycles of Kola NPP power units, with using new type of fuel, and gives some recommendations for improvement of routine fluence calculation procedures.