An electronic ballast system for signage light includes a first lamp string, a second lamp string, a first inverter and a second inverter. The first lamp string includes at least one first lamp tube. The second lamp string is connected with the first lamp string in series, and includes at least one second lamp tube. The first inverter is connected with the first lamp string for driving illumination of the first lamp string. The second inverter is connected with the second lamp string for driving illumination of the second lamp string. A frequency difference between a frequency of the first inverter and a frequency of the second inverter is in a range between 500 Hz and 5 kHz.