The paper describes the results obtained in an investigation of laser remelting of specimens made of 12% Ni maraging steel suitable for the manufacture of highly thermomechanically loaded machine parts or tool parts. The aim of the investigation was to establish the state of differently heat treated maraging steel after a laser repair processes including melting of the material. An analysis of the specimens with an optical microscope after laser remelting showed, regardless of the initial condition, a cellular-dendritic microstructure in the remelted track. In the heat-affected zone surrounding the laser-remelted track the microstructure varied considerably also regardless of the initial condition. A microstructure analysis supported by microhardness measurements made it possible to define several microstructural zones or sub-zones in the heataffected zone. The measurement of residual stresses using the relaxation hole-drilling method close to the laser-remelted track was used to study the influence of the initial material state on the residual stresses after laser remelting.