Abstract: The hypervelocity impact(HVI) of meteoroid/orbital debris(M/OD) on spacecraft wall could cause severe damage.The failure of pressure vessels,the key parts threatened by M/OD,would lead to a catastrophic failure of spacecraft.The HVI characteristics and failure modes of the spherical pressure vessel were presented.The hole diameters under different projectile impact parameters were achieved according to the HVI tests of unpressurized vessels,then the ballistic limit diameter of projectile at a velocity 6.5km/s was analyzed.HVI tests of gas-filled pressurized vessels were also carried out to analyze the impact parameter leading to a catastrophic failure of the vessel.Finally,the prediction model of hole diameter was achieved by means of HVI test data fitting,which provided reference for M/OD shielding design of spacecraft