The study concerns the problem of oil production rate increase from the Low Oligocene reservoir of the largest Vietnam offshore White Tiger field as an example of low permeable clay reservoir. The features of waterflood performance and bottom-hole zone permeability changes in dependence with mineralization of reservoir, injected and drilling mud make-up waters have been described. It has been found that physicochemical stimulation methods with surfactants, alkali and high temperature polymers should be used for oil production increase. The software has been developed for calculation of such type reservoir development programs.