A CT detection device (100) and a locking assembly for the CT detection device (100) are provided. The CT detection device (100) includes: a CT imaging system (110) including a radiation source, a detector, and a rotating frame (111), wherein the radiation source and the detector are mounted on the rotating frame (111), and a periphery of the rotating frame (111) is provided with at least one first hole (112); a support stand (120), wherein the rotating frame (111) is fixed on the support stand (120) through a slip ring bearing, and a periphery of the support stand (120) is provided with at least one second hole (122) aligned with the at least one first hole (112); and a first sleeve (130) detachably engaged in the aligned first hole (112) and second hole (122), wherein the first sleeve (130) includes a first cooperating portion (133) cooperating with a first locking portion (150) to lock the rotating frame (111) during a replacement of the slip ring bearing.