[en] Radiation-hygienic problems are discussed of the nuclear power plants (NPP) decommissioning: NPP power units, research and test reactors, ship nuclear power plants (at submarines, ice-breakers, research and transport ships). Attention is paid to the choice of optimum variant of the NPP decommissioning. Three variants of the nuclear reactor decommissioning are available: shutdown for 30-50 years with further total dismantling; partial dismantling with further limited use of the NPP equipment and site for nonnuclear purposes; total dismantling just after the reactor shutdown with the use of site after the proper treatment. Methods of the dismantling are also considered. Special attention is paid to the transportable NPP decommissioning. Problems of the waste disposal are discussed as well as radiation doses to personnel and population. Environmental impacts are also under consideration