Disclosed are a method and system for controlling a display condition which is pre-written into a passive light board by a mobile device. A display status is pre-written into a passive light board which is not powered by electricity before, and a control application program loaded into the mobile device is provided for a user to input a brightness parameter and a color temperature parameter. The light board which is not powered by electricity before can carry out the presetting of the display condition, and related manufacturers can set the light boards quickly and easily after the light boards exit the factory, and the light boards can display according to the conditions in compliance with the brightness parameter and the color temperature parameter after the light boards are powered on.