Polyelectrolytes are polymers of oppositely charged ions and their properties differ profoundly than their repeating units. Over recent years, much advancement has been made in the synthesis, characterization and application of polyelectrolytes and polyelectrolyte complexes (PECs). There are two kinds of PECs structure: ladder-like structure and scrambled egg model. There are number of elements that influence the synthesis and stability of PEC. Polyelectrolyte complexes are classified based on the type of macromolecules and bonds involved in complexation. It has many applications as flocculation agents, dispersant agents and super-plasticizers. This present article focuses mainly on the polyelectrolytes and polyelectrolyte complexes, their preparation and uses.