Metalorganic chemical vapour deposition (MOCVD) from three organometallic precursors has been applied to the growth of CuGaSe2. Polycrystalline thin films were obtained by co-deposition onto ZnO-coated glass substrates. Structural, morphological, optical and photoluminescence characterizations reveal that the properties of the material strongly depend on the composition. The various characteristics will be detailed. Stoichiometric CuGaSe2 was obtained, as shown by XRD, with a gap of about 1.68 eV. A two-phase region composed of CuGaSe2 and CuCa3Se5 was evidenced for Ga-rich compounds. The absorption edge shifts toward higher energies when the Ga-content increases and for CuGa3Se5 a direct optical gap was found at about 1.85 eV. Photoluminescence measurements show only a large and intense peak from Cu-rich to Ga-rich compositions which is attributed to a donor-acceptor transition.