We examined the effects of LED light spectrum and alternate lighting on the proliferation of protocorm-like bodies (PLBs) and formation of shoot and root on explants of Cymbidium Sweet Waffle ‘Tarte’in order to find the optimal lighting condition for micropropagation of the orchid. We maintained the treatments at 25±1℃ for 24 hours light period. We found that proliferation of PLBs was increased most under monochromatic green LED light (peak wavelength: 517 nm) and alternate green LED light and red LED light (peak wavelength: 631 nm). We also found that shoot formation was increased most under monochromatic red LED light and alternate green LED light and red LED light. Root formation was increased most under blue LED light (peak wavelength: 460 nm). Based on these findings, we concluded that alternate green LED light and red LED light is the optimal lighting condition, because PLB proliferation and fresh weight increase are important for micropropagation of orchids.