Abstract: Ambient ionization has been developed for direct MS analysis of the analytes in untreated samples, and represents a promising solution for simplification or elimination of sample pretreatment procedures in on-site analysis. Since desorption electrospray ionization (DESI) and direct analysis in real time (DART) were reported in 2004 and 2005, respectively, more than 40 ambient ionization methods have been developed. Sample pretreatment and chromatographic separation, traditionally required for MS-based analysis can be bypassed now. Dielectric barrier discharge ionization (DBDI) is a non-surface contact ambient ionization technique, which can achieve desorption/ionization of liquid, solid and gaseous samples in a few seconds by the stable low temperature plasma generated by dielectric barrier discharge (DBD) in inert gases at atmospheric pressure. The mechanism of DBDI is related to a polarization of the dielectric barrier (glass wall) followed by charging of the inner wall. The amount of charges formed at the inner glass wall by polarization/charging is proportional to the change of the voltage. Therefore, instead of the use of an ordinary sinusoidal generator a square wave generator would be of great interest. Combined with a smaller dimension of the capillary not only a pin-ring shape but also a ring-ring shaped DBD can be operated more reproducibly and in case of using He as plasma gas, it can be operated in a homogeneous plasma mode which is preferable for soft ionization. Sample analysis by the DBDI source coupled to MS does not require complicated sample preparation and can be realized in-situ, real-time, rapid and non-destructive detection under ambient conditions. DBDI has become very popular for applications in analytical science because of its outstanding features, including flexibility and simplicity of setup, good portability, and high chemical activity. DBDI source has been widely used in various of research fields such as food safety, public security, pharmaceuticals analysis, environmental monitoring, life science, and so on. The versatility of DBDI has been thoroughly revealed for a series of applications. This paper reviewed the origin, ionization mechanism, classification, influencing factors and application of DBDI, and discussed its future development trend.