Disclosed are a smart spindle with a replaceable battery, and a smart Rubik's cube. The smart spindle comprises a core (100), a sensor (200) and a main control module (310), wherein the core (100) comprises a housing (110) with a cavity (111); the main control module (310) is mounted inside the cavity (111); the sensor (200) is electrically connected to the main control module (310); the sensor (200) is mounted at the core (100); the cavity (111) is also used for mounting a battery (400), the housing (110) is provided with a notch (112) for having access to the battery (400), and the notch (112) is in communication with the cavity (111); or, the exterior of the housing (110) is used for mounting the battery (400), and the housing (110) is provided with a through hole (113), such that the cavity (111) is in communication with the exterior of the housing (110) via the through hole (113). When the power for the smart Rubik's cube is insufficient, a player can remove the used battery and replace same with a fresh battery, such that the smart Rubik's cube can continue to be used immediately, without the need to perform charging and the need to stop use for a period of time, thereby facilitating the use by the player.