We report on the ultraviolet photoluminescence (UV-PL), Raman and structural properties of wurtzite MgxZn1-xO nanopowders of average size ∼ 30 nm that were synthesized via the thermal decomposition method. For the studied composition range of, the room temperature UV-PL was found to be tuned by ∼ 0.24 eV towards the UV-spectral range, and the PL emission was established to be due to an excitonic-type recombination mechanism. The first-order LO Raman mode was found to exhibit a blueshift of ∼ 33 cm-1. The LO-mode of the nanopowders is discussed in terms of a mixed A1-E1 symmetry phonon known as a quasi-LO mode. The observed 30 cm-1 blueshift indicates that the E1 is the principle symmetry component in the Raman scattering of the MgxZn1-xO nanopowders.