The utility model belongs to a component of a valve used for a carrier rocket, and particularly relates to a superfluous object prevention device for a rod-type kinematic pair. The superfluous object prevention device for the rod-type kinematic pair comprises a rod, wherein the rod is sleeved with a guide sleeve, a groove and a boss are arranged on the excircle cylindrical surfaces at the two ends the guide sleeve, S-shaped dustproof rings are installed at the two ends of the guide sleeve respectively, an inner boss of the S-shaped dustproof ring is inserted into the groove of the guide sleeve, and the boss on the guide sleeve is inserted into an inner groove of the S-shaped dustproof ring. The superfluous object prevention device has the advantages that the rod moves in the guide sleeve, as the dustproof rings tightly hold the rod, superfluous objects are prevented from entering a fit clearance between the rod and the guide sleeve, and the rod is prevented from clamping motion caused by the superfluous objects.