A system and method for testing hybrid sleep modes of an electronic device sets a switch time of switching a suspending to RAM (S3) sleep mode to a suspending to disk (S4) sleep mode. A computer sends a power management event (PME) signal to control the electronic device to be in the S3 sleep mode. If a system time of the electronic device reaches a switch time of switching the S3 sleep mode to the S4 sleep mode, the computer detects if the electronic device is in the S4 sleep mode. If the electronic device is in the S4 sleep mode, the computer sends an awake signal to control the electronic device to be in a normal work mode. A display of the computer displays that the electronic device is in the S3 sleep mode, the S4 mode, or the normal work mode.