A hard disk carrier includes a tray bracket and a turnover bracket rotatably arranged on the tray bracket. The tray bracket includes a first side wall, a second side wall parallel to the first side wall, and a bottom wall connecting the first side wall and the second side wall. wherein The turnover bracket includes two turnover arms rotatably arranged on the bottom wall between a first angle at which the turnover arms being received in the bottom wall and a first receiving space is defined between the first side wall and the second side wall and a second angle at which the turnover arms turns out from the bottom wall and a second receiving space is defined between the two turnover arms. A size of the second receiving space is different from that of the first receiving space.