Transplants of tomato cultivar ‘Hybrid Tarasenko’ and ‘De Barao’ were grown under the additional lighting of different high-intensity light sources in greenhouses. As lighting sources were tested: mercury arc lamps with a luminophores covering (MALF 400), standard high-pressure sodium lamps (HPS 400) and high-pressure sodium lamps with additive of Cesium (HPS-Cs 400) and amalgam content: Hg-20 %, Na-75 %, Cs-5%. It was established that introduction of Cesium 5% in the amalgam composition of high-pressure sodium lamps, leads to increase of radiation intensity in red (600-700 nm) and near Infrared region to 58%. The growth dynamic and the most important morphological attributes of the transplant were investigated. Our investigations revealed that the increase of red light proportion in spectral composition of such lamp radiation promoted an intensification of tomato plants growth processes and photosynthesis. Increase in yield was result of the carried-out greenhouse experiment with tomatoes plants which is grown up when lighting by HPS-Cs 400 lamps. The yield of ‘Hybrid Tarasenko’ and ‘De Barao’ tomato cultivars, grown under HPS-Cs 400 lighting, exceeded the yield of plants grown under HPS 400 lighting by 7.4% and 6%, respectively. The irradiation of ‘Hybrid Tarasenko’ and ‘De Barao’ tomatoes plants by HPS-Cs 400 lamps promoted to the more significant yield increase on 22.8% and 24.5%, respectively, as compared with the plants cultivated under the lamps of MALF 400.