A start-up control apparatus includes a control chip, an advanced configuration and power management interface (ACPI) controller, and a firmware. The control chip includes an analysis module and a control module. The ACPI controller is used for receiving a trigger signal and sending a start-up signal corresponding to the trigger signal to the control module if a computer system is powered off. The firmware is used for sending a status signal to the analysis module after the firmware finishes initialization. The analysis module is further adapted to send the trigger signal to the ACPI controller after receiving the status signal, and the control module is adapted to send the start-up signal to a power supply to provide power for powering on the computer system.