Using sustained release tablets of Ginkgo bibolia extract as model drug,discuss technical feasibility of using biotic index to evaluate sustained release tablets. Chosing two pharmacological indicatrix: antioxidant ability and inhibition of platelet aggregation, to investigate the influence factors on experimental result, optimize the method and experiment condition, and set up pharmacological indicatrix evaluation method. Using those methods to determinate biological effects of dissolved liquid. Drawing release curves and biological effects curves, discussing their correlation. A good correlation was observed, illustrating that pharmacological indicatrix could evaluate sustained release tablets.