In every growth-stage, a plant requires a different amount of PAR intensity for photosynthesis. The light irradiance is not only obtained from sunlight but can be manipulated using LED in an enclosed cultivation room. Each LED has a different value of Photosynthetically Active Radiation (µmol/m2 s) although they have the same irradiance in Lux. In this paper, a simple wireless system for PAR monitoring and remotely control intensity was built using silicon-based photo transistor sensor, controller and an Android application which is able to adjust the brightness of the three LEDs as desired from distance. The peak wavelengths of the three LEDs are 617 nm (red), 465 nm (blue), and 520 nm (green). The system is able to record irradiance in Lux and PPFD (µmol/m2 s) of PAR spectrum. Compared to the commercial PAR-meter, the system has good measurement accuracy in red room, blue room and green room are 99.64%, 97.61%, and 99.58%, respectively. The opened-loop irradiance control system for cultivation room also has a good response dynamic. the red LED has the shortest rise time of 2.95 second and the low error steady state than others, 2,33 Lux. It means, the red LED control system can give a quick response and good stability irradiance. In the other hand, the green LED has the highest rise time fo 3.7 second and the highest error steady state of 12,95 Lux, compared to the other LED. The green LED control system can do slower response to reach its maximum irradiance and the worst stability performance while irradiating the cultivation room.