The effectiveness of phototherapy depends on three factors: the spectrum of light, the energy output of the light, and infans in areas exposed to phototherapy. "Simulator Double Surface Phototherapy" is one means of photo therapy has the advantage that the radiation from the two sides, the top surface of infant and under baby. So that the surface area of light illuminated the more spacious. Spectrum of light obtained from three lamps bluelight, two at the top and one bi bottom with irradiation distance of 10 cm from the bottom surface of the baby's body and 35 cm from the top surface of the baby. This tool has four options of therapy time is 6 hours, 12 hours, 18 hours and 24 hours yan selected via buttons up and down. "Double Surface Phototherapy Simulator" uses a stopwatch measuring tool to determine the accuracy of exposure time. Values obtained from measurement error timer is equal 0,07 to 6 hours, 0,08 at 12 hours, 0,09 at 18 hours, 0,1 at 24 hours. Based on the measurement results can be concluded that the tool "Simulator Double Surface Phototherapy" can be used