1, 2-Distearoyl-sn-glycero-3-phosphoethanolamine-Poly(ethylene glycol) (DSPE- PEG) is a widely used phospholipids-polymer conjugate in drug delivery applications. It is a biocompatible, biodegradable and amphiphilic material which can also be functionalized with various biomolecules for specific functions. With the emerging interest in use of nanocarriers for therapeutic drug delivery and imaging DSPE-PEG has become a very useful material for the formulation of these nanocarriers for achieving prolonged blood circulation time, improved stability and enhanced encapsulation efficiency. This review will focus on the relationships between the structure of DSPEPEG and its noticeable effects on these nanocarriers' properties, and the recent progress on the development of DSPE-PEG and its derivatives in delivery systems.