Gold therapy is employed primarily in progressive rheumatoid arthritis which is refractory to the conventional measures such as aspirin-like agents. The benefical effects of gold therapy have been demonstrated by careful double blind trials on rheumatoid arthritis. However, its mechanism of action is poorly understood. A limitation to use the gold salt is its potential hazards and toxicity and great care should be given during gold therapy. This study was done to evaluate the effectiveness of gold salt on rheumatoid arthritis and its adverse effect during therapy. Forty-five rheumatoid arthritis patients who received gold sodium thiomalate at Ewha Womans University Hospital from. December 1983 to June 1985 were analyzed in this study. The results are as follows: 1) The incidence of rheumatoid arthritis was higher in female than in male with the ratio of 5:1 and the higher incidence was seen in the thirties and fourties(58%). 2) The mean duration of disease was 3.1 years, ranging 2 weeks to 11 years. 3) Common type of rheumatoid arthritis were the Classic and Definite type, and they were 18 cases(40%) and 15 cases(40%), respectively. The Probable(9 cases) and the Possible types(3 cases) were less common. 4) The average onset of clinical improvement was 12 weeks after gold therapy and the mean cumulative dose at this period was 550mg. 5) Thirty patients out of 45 patients showed marked to moderate clinical improvement after completion of gold therapy, whereas 12 patients did not respond. 3 patients were intolerated to gold therapy and discontinued due to severe adverse reactions. 6) The adverse reaction was observed in 32 of 45 patients receiving gold therapy for rheumatoid arthritis and the most common side reaction was dermatologic manifestations(21 cases). 7) There was no correlation between eosinophilia and the occurrance of the side effects.