TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractOn the base of molecular structure design , we have synthesized hydrophobically associating water-soluble polymers. The solution properties of hydrophobically associating watersoluble polymer as a function of electrolytes concentration temperature and shear rate have been investigated .The enhance in oil recovery obtained in core flow experiment with the polymers solution is higher . This polymer is developed for use under hostile reservoir conditions.