Poly(2-oxazoline) s are emerging innovative biomaterials that show analogous and even preferable properties compared to well-known counterparts, especially poly(ethylene glycol). This polymer can be synthesized in a living and hence controlled manner using the cationic ring-opening polymerization method. In addition, various polyoxazolines are water-soluble or amphiphilic and relatively non-toxic, making them attractive as biomaterials. Polyoxazolines (10 and 20 kDa) are safe when used intravenously to rats and can be used for several biomedical applications. These results from various papers and patents conclude that POx is a favorable biopolymer. The present review aims to highlight the synthesis, structure, and properties of polyoxazolines, such as different derivatives of POx used in tissue engineering. Different polymerization methods and smart behaviors of POx are described as well. Finally, it aims to introduce the significance and potential of POx in biomedical applications like drug delivery, protein delivery, and gene delivery using a number of leading references of recent years.