The authors investigated the effect of light-emitting diode irradiator with maximum in the region of red (λmax 6305 nm, 6605 nm) and blue (λmax 4505 nm, 4705 nm) light on growth processes and activity of photosynthetic apparatus in potato plants of the Nevskii early variety. It was made a conclusion, that application of light-emitting diode irradiators in controllable conditions of phytotron may be useful technique during potato growing subject to changes of spectrum composition in plant ontogenesis.