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We examine 14 plates of the globular cluster M3 (NGC 5272) taken withthe 40 cm refractor at the Sheshan station of Shanghai Astronomical Observatory.The plates span over a period of about 77 years. The positions and absolute propermotions of eight stars in the Hipparcos Catalogue and of 49 stars in the Tycho-2Catalogue are used as the reference frame. The astrometric reduction is made withthe central overlapping principle. The absolute proper motions of 534 stars in aregion of about 100′× 100′ around the cluster are measured. With the new propermotion data the membership probabilities of the stars are determined. The averageabsolute proper motion obtained for the cluster is -0.06±0.30 mas yr-1 in R.A.and -2.6±0.30 mas yr-1 in Decl. By combining this result with the known distanceand radial velocity of the cluster, we also obtained the Galactic orbit of M3 for achosen three-component Galactic potential.