From the viewpoint of "supramolecular chemistry,", control of crystal and electronic structures of molecular conductors is described. We have developed a variety of cation and anion radical salts containing supramolecular assemblies. For the formation of the supramolecular structures, two types of supramolecular synthons, 1) iodine-based halogen bond-I...X- (X = CN, Cl, Br, S), and 2) tellurium-based secondary bond Te...S, have been examined, These compounds have indicated that supramolecular assemblies provide novel molecular packings and efficiently tune the donor or acceptor arrangement. We also found that the formal charge of conducting molecules can be controlled by the tuning of supramolecular assemblies.