We present a novel square superlattice plasma photonic crystal (PPC) fabricated by periodic arrangement of different-sized gas discharge tubes and Al2O3 dielectric rods. The effects of the plasma, the number and location of Al2O3 rods, and the angular orientation of PPCs on the microwave transmission characteristics have been demonstrated. For the simple square lattice, a PBGa in the range of 13.40–14.20 GHz is obtained. For the square superlattice, an additional PBGb in the range of 14.35–15.10 GHz develops. While PBGa and PBGb are primarily dependent on the square sublattices of plasma rods and Al2O3 rods, respectively, a synergistic effect arising from the interplay between these two sublattices is suggested. Moreover, a new PBGc is achieved by changing the rotation angle of the PPC to 45° The multiple parameters control of square superlattice PPC may inspire new strategies for designing fully bandgap-tunable PCs and may find potential applications in various fields.