The invention aims at providing an expressway hollow slab girder longitudinal splicing structure and method. The expressway hollow slab girder longitudinal splicing structure comprises an old bridge hollow slab girder, a new bridge hollow slab girder, multiple self-tapping bolts, multiple pieces of embedded connection rebar, concrete pre-pavement layers, reinforcing meshes, concrete wet connectionconnectors and hollow pipes; the middles of the old bridge hollow slab girder and the new bridge hollow slab girder are provided with filling gaps, the multiple self-tapping bolts are connected withone side end of the old bridge hollow slab girder, the multiple pieces of the embedded connection rebar are arranged at one side end of the new bridge hollow slab girder and are welded to tails of theself-tapping bolts in a one-to-one correspondence mode, the concrete pre-pavement layers are arranged on the outer side of the upper end of the old bridge hollow bridge and the outer side of the upper end of the new bridge hollow slab girder, the reinforcing meshes are arranged in a pavement space formed between the two concrete pre-pavement layers, the two side ends of the reinforcing meshes areconnected with fixed rebar groups of the two concrete pre-pavement layers in a one-to-one corresponding mode, the concrete wet connection connectors are poured into the pavement space and the fillinggaps, and multiple pairs of hollow pipes are arranged in the longitudinal direction and penetrate into the concrete wet connection connectors. The expressway hollow slab girder longitudinal splicingstructure is stable in longitudinal seam splicing quality.