This study investigates the Sequence stratigraphy and depositional environment of Wadi Es Sir Formation (Turonian) in Irbid City. The Wadi Es Sir Formation consists of thick bedded to massive limestone, dolomitic limestone and dolomite. Based on Petrographic study Eight facies wreeidentified in the studied sections These are mudstone, gastropoda peloidal packstone, algal-lithoclast wackestone to packstone, peloidal foraminifera wackestone to packstone, bioclastic wackestone to packstone foraminifera wackestone, rudist framestone and pelletal grainstone. These facies weredeposited on the followingenvironments: restricted marine, shallow open marine and shoal environments.Sequence stratigraphystudy in Wadi Es Sir Formation identified forth-order cycles which are asymmetrical and consist of transgressive systems tract (TST) represented by shallow open marine and sometime shoal facies, followed by highstand systems tract (HST) represented by restricted marine facies. They are bounded below by a transgressive surface (Ts) and above by marine flooding surface (mfs). They represent successive episodes of relative sea level rise and stillstands. The nature of these cycles (composition and symmetry) reflects the combined effect of local tectonics and eustasy. Manuscript profile