The utility model discloses a cube star magnetic field strength meter deployment mechanism, including end cover, box body, connecting rod, fixed hinge, rotatory hinge, stay, rotation axis, check lock lever, spring and torsional spring, when having no job, the utility model discloses an all the laminating is surperficial at the satellite to burn the linear system. After going up to the air, burning all work of linear system, burning the line and blown, magnetic field strength counts the restraint that receives and relieves. Under the effect of turning round, rotatory hinge drive connecting rod and box body pop out, when playing 90 position, the blind hole promotes the check lock lever and pops out with through -hole the central axis coincidence, spring, and the cube star magnetic field strength meter deployment mechanism lock is died. The utility model discloses an outside target of celestial body is expanded with the magnetic field strength meter, the influence of celestial body internal magnetic field to the magnetic field strength meter can be completely cut off effectively.