[en] The transport properties of free charge carriers, photo- and cathodo-luminescence (CV) in GaN and AlN films obtained by MOCVD technique on sapphire and Si substrates, are investigated. The concentration of free charge carriers in GaN is of order 10¹⁷-10¹⁹ cm^-3 whereas AlN thin films are insulating. The Hall mobility of electrons are 80-140 cm²/V s). In undoped GaN films the spectral composition of CL is close to photoluminescence (PL) when excited in the region of band-band transitions. The decay time constant of the 3.44 eV UV emission attributed to the bound exciton is considerably less than 1 ns, whereas the 3.26 eV violet (VI) band shows a slow hyperbolical decay over about 1 μs. The known yellow band appears at 2.25 eV due to transitions via localised states. In AlN the spectral composition of the broad CL band is close to that from bulk materials attributed to charge transfer transitions in deep oxygen-related donor-acceptor centres