Abstract: The established 6 relationships of water cut and recovery percent of reserves have been summarized.These relationships were transformed into those between water cut and recovery percent of recoverable reserves, and these curves investigated.Such relationship can reflect different water cut trends, while the use of instant water cut affected the computing accuracy which can be removed by using the culmulative values of oil production, water production, liquid production and water injection rate.

Key words: Water drive, Water cut, Recovery percent, Recoverable reserve, Curve