The invention provides an electrical connection device with an automatic separation mechanism, which includes a plug / socket and an automatic separation mechanism. The automatic separation mechanism includes a bracket, a floating plate, a locking mechanism, a connecting rod and an installation shell, and the bracket includes a top plate and a bottom plate. The top plate and the bottom plate are fixedly connected by a guide rod. The axial direction of the guide rod is perpendicular to the course of the missile body. The floating plate slides on the guide rod. There is a locking mechanism, one end of the locking mechanism is fixedly connected with the floating plate, the installation shell is hinged with the floating plate through the connecting rod, the plug / socket is fixed on the installation shell, and the directional movement of the projectile can push the installation shell to touch the locking mechanism to unlock, release Restrictions on the movement of the floating board. The invention provides an electrical connection device with an automatic separation mechanism, which realizes simultaneous launch of projectiles and separation of electrical connectors, saves launch time, and is more suitable for modern war requirements.