Abstract: The present disclosure discloses an apparatus for read/write operations on a serial attached small computer system interface (SAS) hard disk through a universal serial bus (USB) interface. The apparatus includes: a case, where the case is internally provided with a printed circuit board assembly (PCBA) mainboard, the PCBA mainboard is provided with a controller, a power management module, an SAS to serial advanced technology attachment (SATA) protocol conversion module, an SATA to USB protocol conversion module, a USB interface and an SAS hard disk access interface, and the controller controls the PCBA mainboard to conduct the read/write operations on the SAS hard disk; and other components. The apparatus facilitates rapid read/write operations on the SAS hard disk by a consumer through the USB interface, and also improves heat dissipation efficiency of an apparatus body.