A child car seat attachment system, comprising: - a base comprising a bottom, a front wall and an opposite rear wall, - a pair of connectors (6, 7) which are designed to move in a direction of translation (X-X) between a position of maximum extension out of the base to a position of maximum retraction into the base, each connector (6, 7) being able to be reversibly attached to anchor means of a car seat, - a pair of tensioning cables (8, 9) located inside the base and operable on the pair of connectors (6, 7), alternating between a loose configuration and a stretched configuration to release the pair of connectors (6, 7) from the anchor means when the pair of connectors (6, 7) moves to the position of maximum extension from the base, - a belt passing through the front wall and having a first free end projecting out of the base, the belt being able to translate in the direction of translation (X-X) to allow the pair of connectors (6, 7) to move in the direction of translation (X-X) between the position of maximum extension from the base and the position of maximum retraction into the base, - a locking mechanism mounted on the base and configured to stop the sliding movement of the belt that brings the free end toward the base and to permit the movement of the belt that brings the free end away from the base, the locking mechanism comprising an unlocking system operable to permit the sliding movement of the belt that brings the free end toward the base, characterized in that it comprises: - a pair of rigid rods (14, 15) rigidly joined to the pair of connectors (6, 7) and sliding relative to the base in the direction of translation (X-X), each rigid rod (14, 15) comprising a first connection end (16, 17) connected to a respective connector (6, 7), wherein each tensioning cable (8, 9) comprises a first end (18, 19) at which it is connected proximate the front wall and an opposite second end (20, 21) at which it is connected to a respective connector (6, 7), - a connecting bar arranged inside the base and designed to move in the direction of translation (X-X), the connecting bar being connected to the second end of the belt, opposite to the first end, and to the pair of rigid rods (14, 15), - a pair of pull-out springs (24, 25), each pull-out spring (24, 25) comprising a fixed end (26, 27) connected to the base and an opposite movable end (28, 29) connected to the connecting bar, the pair of pull-out springs (24, 25) being configured to reversibly move from an extended configuration, in which the pair of connectors (6, 7) is in the position of retraction into the base, to a retracted configuration in which the pair of connectors (6, 7) is in the position of maximum extension out of the base, when the unlocking system is actuated. - a base comprising a bottom, a front wall and an opposite rear wall, - a pair of connectors (6, 7) which are designed to move in a direction of translation (X-X) between a position of maximum extension out of the base to a position of maximum retraction into the base, each connector (6, 7) being able to be reversibly attached to anchor means of a car seat, - a pair of tensioning cables (8, 9) located inside the base and operable on the pair of connectors (6, 7), alternating between a loose configuration and a stretched configuration to release the pair of connectors (6, 7) from the anchor means when the pair of connectors (6, 7) moves to the position of maximum extension from the base, - a belt passing through the front wall and having a first free end projecting out of the base, the belt being able to translate in the direction of translation (X-X) to allow the pair of connectors (6, 7) to move in the direction of translation (X-X) between the position of maximum extension from the base and the position of maximum retraction into the base, - a locking mechanism mounted on the base and configured to stop the sliding movement of the belt that brings the free end toward the base and to permit the movement of the belt that brings the free end away from the base, the locking mechanism comprising an unlocking system operable to permit the sliding movement of the belt that brings the free end toward the base, - a pair of rigid rods (14, 15) rigidly joined to the pair of connectors (6, 7) and sliding relative to the base in the direction of translation (X-X), each rigid rod (14, 15) comprising a first connection end (16, 17) connected to a respective connector (6, 7), wherein each tensioning cable (8, 9) comprises a first end (18, 19) at which it is connected proximate the front wall and an opposite second end (20, 21) at which it is connected to a respective connector (6, 7), - a connecting bar arranged inside the base and designed to move in the direction of translation (X-X), the connecting bar being connected to the second end of the belt, opposite to the first end, and to the pair of rigid rods (14, 15), - a pair of pull-out springs (24, 25), each pull-out spring (24, 25) comprising a fixed end (26, 27) connected to the base and an opposite movable end (28, 29) connected to the connecting bar, the pair of pull-out springs (24, 25) being configured to reversibly move from an extended configuration, in which the pair of connectors (6, 7) is in the position of retraction into the base, to a retracted configuration in which the pair of connectors (6, 7) is in the position of maximum extension out of the base, when the unlocking system is actuated.