Background/Aims : Various commercial serologic tests have been developed for the diagnosis of Helicobacter pylori (H. pylori) infection, but clinical data regarding their accuracies are often lacking. Methods : Sixty-four patients who visited Severance Hospital and underwent gastroscopy were enrolled. Multiple biopsy specimens were obtained from antrum and body for histology and rapid urease test (CLO test). As serologic tests, QuickVue, EZ-HP, GAP, Cobas Core II, and Pyloragen tests were used. Results : H. pylori infection were diagnosed in 40 (62.5%) patients by histology or CLO test. The sensitivities of five serologic tests were as follows: QuickVue, 75.0%; EZ-HP, 90.0%; GAP, 85.0%; Cobas Core Ⅱ, 80.0%; Pyloragen test, 80.0%. The specificities of those tests were as follows : QuickVue, 66,7%; EZ-HP, 45.8%; GAP, 62.5%; Cobas Core Ⅱ, 70.8%; Pyloragen, 70.8%. The accuracies of them were as follows: QuickVue, 77.5%; EZ-HP, 73.4%; GAP, 85.0%; Cobas Core Ⅱ, 76.6%; Pyloragen, 76.6%. The five serologic tests showed no statistically significant difference in their sensitivity and specificity. The QuickVue and the EZ-HP were comparable in their accuracy. However, the EZ-HP test revealed higher sensitivity and lower specificity than the QuickVue test. The GAP test showed better sensitivity compared to those of other quantitative tests, but all of them were comparable in terms of poor specificities. Conclusions: The five serologic tests showed lower specificities in Korea than in western countries. Thus, the development of serologic tests with good diagnostic accuracy is necessary in Korea.