The aim of this investigation was to determine the influence of additional LED (Light Emitting Diode) lighting on stem diameter and height as well as yield and fruit weight of tomato grown hydroponically in coco peat. The trial was conducted in a greenhouse using hydroponic technology production in cocoa peat. LED lamps equipped with blue and red diodes were placed above rows. Plants received additional light averagely 5 hours per day during 112 days until the third harvest was finished. Additional LED lighting significantly influence tomato by increasing the yield, fruit weight and stem diameter. In addition, plants treated with LED lighting had significantly shorter stem, indicating balanced growth and development. However, economic analysis showed that, even being low energy consumers, LED lamps used in this investigation are not efficient enough in energy considering realized yield and net profit. Therefore, LED lamps usage is recommended only during tomato transplants and similar species production.