The aim of this study was to investigate the impact of the use of two Kampo medicines on oral mucositis, tongue coating bacteria, and gingiva condition in patients with esophageal cancer undergoing chemotherapy.Twenty-three esophageal cancer patients who receive chemotherapy at Tokushima University Hospital, were included. The participants, who received professional oral healthcare, were randomly divided into three groups:7 subjects received Daiokanzoto sherbets, 7 subjects received Hangeshashinto sherbets, and 9 subjects received nothing (control). The numbers of total bacteria and specific periodontopathogenic bacteria in tongue coating were determined in addition to clinical parameters.No difference on the onset of oral mucositis was found among the three groups. However, tongue coating index, gingival index (GI), plaque index, the number of total bacteria, Fusobacterium nucleatum and Campylobacter rectus were decreased during chemotherapy. More specifically, GI as well as the number of F. nucleatum and C. rectus were decreased significantly in the Daiokanzoto group when compared to the control group (psize 8 < 0.05). No such differences were observed for the group receiving Hangeshashinto.This clinical trial showed that Daiokanzoto might be effective in attenuating gingival inflammation and reducing the levels of periodontopathogenic bacteria in patients with esophageal cancer. J. Med. Invest. 65:184-190, August, 2018.