Using a combination of MOC-hydride epitaxy and pulsed laser deposition, InGaAs/GaAs heteronanostructures with a (Ga,Mn)As layer on the surface are obtained, and the influence of the action of a pulsed excimer laser (with a wavelength of 248 nm, pulse duration of ~30 ns, and energy density in the range of 200–360 mJ/cm 2 ) on their radiative, structural, and galvanomagnetic properties is studied. The study is carried out using photoluminescence spectroscopy complemented by the possibility of analyzing radiation polarization characteristics of the structures. The crystalline perfection of the initial and laser-irradiated samples was studied with the use of Raman scattering spectroscopy. The elementary composition of the structures and its distribution over the depth were studied by secondary ion mass spectrometry. The influence of pulsed laser annealing on ferromagnetic properties of heteronanostructures is characterized by the behavior of magnetic field dependences of the Hall resistance and magnetoresistance at temperatures of 10–300 K within the range of magnetic fields of ±3600 Oe. At room temperature, the study was carried out in magnetic fields reaching ±28 000 Oe. The calculated temperature distributions along the sample thickness and in time using the laser annealing model based on solving the problem about heat propagation in a one-dimensional GaAs system with allowance for the (Ga,Mn)As layer on the surface are obtained using original data on the thermal conductivity of structures with a (Ga,Mn)As layer. The data were obtained by the modified frequency division technique (the 3ω method).