Sulfur is produced as a byproduct of oil refining, of which 7 million tons are dumped above ground each year. Since sulfur-containing polymers can be synthesized from sulfur, a surplus resource, they are attracting attention from the perspective of Sustainable Development Goals (SDGs). Furthermore, since sulfur exhibits unique properties such as high capacitance, high refractive index, and reversible bond formation and dissociation, it is expected to be applied to battery materials, lenses, and self-healing materials. Sulfur-containing polymers can be easily obtained by simply heating sulfur to high temperatures. However, the high-temperature conditions are environmentally hazardous, and the resulting sulfur-containing polymers have low solubility, instability, and low molecular weight, making it difficult to implement them in society despite their potential to create highly functional materials. In this review, we describe supramolecular sulfur-containing polymers developed by the authors to solve these problems by introducing the supramolecular concept of self-assembly of molecules through weak interactions into sulfur-containing polymers.