A detecting system for detecting the connection of two connectors includes a number of first and second linking lines. The detecting system includes a number of first detection switches, a number of pull-down resistors, a number of second detection switches, a number of pull-up resistors, and a detection module. Each first linking line is grounded via each first detection switch and each pull-down resistor in series. The terminals of the pull-down resistors connected to the first detection switches are defined as first detecting ends. Each second linking line is electrically coupled to a high potential via each second detection switch and each pull-up resistors in series. The detection module with a threshold value preset is configured for comparing the voltage value at the first detecting ends with the threshold value, and outputting a result to determine whether the first linking lines are electrically connected to the second linking lines respectively.