Abstract: The present invention discloses an ejection deployment and retrieval mechanism for a tethered satellite with repeatable unlocking and locking and a working method thereof, the present invention includes a separation ejection docking assembly and a sub-satellite; the separation ejection docking assembly includes an ejection sleeve, a locking mechanism, and a sub-satellite connector, the ejection sleeve adopts a two-stage internal-external sliding connection and provides initial kinetic energy to the sub-satellite by compressing a spring; the locking mechanism is mounted inside the ejection sleeve, one end of the sub-satellite connector is connected to the sub-satellite, and another end of the sub-satellite connector is slidably engaged with the locking mechanism to complete the locking/unlocking operations of the sub-satellite.