Small-angle X-ray scattering was used to investigate the nanostructures of complexes formed by slightly crosslinked anionic copolymer gels of poly(sodium methacrylate-co-N-isopropylacrylamide) [P(MAA/NIPAM)] with cetyltrimethylammonium bromide (CTAB), and didodecyldimethylammonium bromide (DDAB), respectively, at room temperature (ϳ 23°C). Several highly ordered supramolecular structures were observed in the polyelectrolyte gel-surfactant complexes. In P(MAA/NIPAM)-CTA systems, in sequence with decreasing charge density of the P(MAA/NIPAM) copolymer chains, structures of the Pm3n space group cubic, face-centered cubic close packing of spheres, and hexagonal close packing of spheres were determined at a charge content of Ն 75, 67, and 50%, respectively. The spheres and rods in these structures were the spherical and cylindrical micelles formed by the self-assembly of CTA cations with their paraffin chains inside. Both the aggregation number and the size of the micelles decreased with a decreasing charge density of the copolymer chains. In the P(MAA/ NIPAM)-DDA systems, the bilayer lamellar structures formed at charge contents Ն 75% transferred to bicontinuous cubic structures of the Ia3d space group at charge contents of 50 -67%. The rods in the Ia3d cubic structures were formed by the selfassembly of double-tailed DDA cations with polar moieties inside. The formation of these highly ordered structures were driven by both electrostatic and hydrophobic interactions of the charged copolymer chains/surfactants and the surfactants/surfactants inside the charged gels. The structures became less ordered by further decreasing the charge content of the P(MAA/NIPAM) chains.