Abstract: Several sulfodehydroabietates were prepared via sulphonation and salt reaction using dehydroabietic acid directly as raw material. The structures were characterized by IR. One-step salt reaction was studied in detail, especially the effect of pH value of system, which is the critical factor. The optimum pH values of different systems were obtained by simulating reaction and comparing to theoretical pH value of generating precipitation. According to body pH value and toxicity, ferrous iron, cobalt, nickel and manganese salts were selected for synthesizing sulfodehydroabietates, which are resistant to gastric juice activity. The pathology and toxicology of dis-ferrous sulfodehydroabietate were studied. The results showed that the toxicology is very low, the inhibition to gastric secretion and inhibition ratio of total acid by ferrous sulfodehydroabietate at 50, 100, 150 mg/kg doses respectively are better than that of cimitidine at 160 mg/kg dose.