A camera assembly comprising: a motor configured to generate a driving power; a motor shaft configured to define a first axis (Ax) extending from the motor and to rotate by the driving power of the motor; a pulley configured to rotate on a second axis (Bx) spaced from the first axis (Ax) according to the rotation of the motor shaft; a belt configured to couple the motor shaft to the pulley and to convert the rotation of the motor into a rotation of the pulley; a camera module configured to be mounted on the pulley and to rotate together with the pulley, characterized in that the camera assembly further includes, an elastic member configured to apply a biasing force to the motor shaft such that the motor shaft is away from the second axis (Bx), a base configured to be fixed at a side of a housing of the camera assembly; a movable member configured to be fixedly coupled to the motor and to be rotatably mounted on the base, a fixed shaft configured to rotatably mount the movable member on a first point of the base; and a movable shaft (20a, 20b) configured to be coupled to the base at a second point spaced from the first point, wherein the movable shaft (20a, 20b) comprises two movable shafts that are received in a first corresponding slot and a second corresponding slot, respectively, and the first corresponding slot and the second corresponding slot are in the movable member such as to support sliding motion of the movable member, and wherein the first corresponding slot and the second corresponding slot are elongated in a circumferential direction according to a same rotation radius extending from the first point, wherein the camera assembly is configured that a tension of the belt and the biasing force of the elastic member are balanced such that a distance between the first axis (Ax) and the second axis (Bx) is adaptively adjusted, the tension of the belt being a force applied in a direction in which the motor shaft moves close to the second axis (Bx) and the biasing force of the elastic member being a force applied in a direction in which the motor shaft moves away from the second axis (Bx). a motor configured to generate a driving power; a motor shaft configured to define a first axis (Ax) extending from the motor and to rotate by the driving power of the motor; a pulley configured to rotate on a second axis (Bx) spaced from the first axis (Ax) according to the rotation of the motor shaft; a belt configured to couple the motor shaft to the pulley and to convert the rotation of the motor into a rotation of the pulley; a camera module configured to be mounted on the pulley and to rotate together with the pulley, characterized in that the camera assembly further includes, an elastic member configured to apply a biasing force to the motor shaft such that the motor shaft is away from the second axis (Bx), a base configured to be fixed at a side of a housing of the camera assembly; a movable member configured to be fixedly coupled to the motor and to be rotatably mounted on the base, a fixed shaft configured to rotatably mount the movable member on a first point of the base; and a movable shaft (20a, 20b) configured to be coupled to the base at a second point spaced from the first point, wherein the movable shaft (20a, 20b) comprises two movable shafts that are received in a first corresponding slot and a second corresponding slot, respectively, and the first corresponding slot and the second corresponding slot are in the movable member such as to support sliding motion of the movable member, and wherein the first corresponding slot and the second corresponding slot are elongated in a circumferential direction according to a same rotation radius extending from the first point, wherein the camera assembly is configured that a tension of the belt and the biasing force of the elastic member are balanced such that a distance between the first axis (Ax) and the second axis (Bx) is adaptively adjusted, the tension of the belt being a force applied in a direction in which the motor shaft moves close to the second axis (Bx) and the biasing force of the elastic member being a force applied in a direction in which the motor shaft moves away from the second axis (Bx).