Poly(4-vinyl pyridine (P4VP) core-polystyrene (PS) shell type polymer microspheres were synthesized by crosslinking the P4VP spherical microdomains of poly(styrene-b-4-vinyl pyridine) (P(S-b-4VP)) diblock copolymers with 1,4-dibromobutane (DBB). The packing structures of well characterized microspheres, both on one layer and also in the bulk were investigated by transmission electron microscopy (TEM). For the AB05 microspheres (diameter of P4VP core = 40.7 nm, aggregation number = 1300), an ordered packing of the microspheres on to a hexagonal lattice was observed for one layer, while in the bulk of the film, AB05 ordered on to a face-centred cubic (f.c.c.) lattice.