A serial advanced technology attachment (SATA) interface tester includes a memory, a signal converter, at least one SATA interface, and an indicator. The at least one SATA interface is adapted to connect with SATA interfaces of a motherboard, and is electrically connected to the memory via the signal converter. The signal converter receives serial signals from the motherboard via the at least one SATA interface and converts them to parallel signals and then passes the parallel signals to the memory to perform a writing process. The signal converter receives parallel signals from the memory and converts them to serial signals and passes the serial signals to the motherboard via the at least one SATA interface to perform a reading process. The indicator is electrically connected to the memory for indicating testing result of the SATA interfaces of the motherboard.