Stomatitis is a common toxicity associated with the administration of certain cancer chemoth-erapeutic agents used in the treatment of malignant tumors. It represents one of the most distressing side effects of cancer chemotherapy and can interfere with the patient's ability to eat, be the cause of much pain and discomfort, and require the use of potent analgesics. The situation also creates favorable conditions for local infection which may lead to septicemia. Several authors have identified the need to estabilish protocols for the control and treatment of the oral discomfort associated with oral mucositis as a result of chemotherapy. Thus this study attempted to development of oral care protocol for chemotherapy patients. The effects of the mouth care using sterile normal saline, nystatine solution on oral stomatitis were investigated in 30 patients on chemotherapy. The subject were devided into three groups; control group: not gargling experimental group A: normal saline gargling (4 times a day) experimental group B: nystatine solution gar-gling(4 times a day) The Oral Assessment Guide (OAG) was used to assess oral status three times (once in the prechemotherapy period, on 5th, 10th day of post chemotherapy) Oral culture was used to assess oral infection on 5th day of postchemotherapy. Data was analyzed on SAS program which used repeated ANOVA, t-test, X2 test. The results are as follows; 1. The incidence of stomatitis was higher in the control group and experimental group A than in experimental group B. (X2=0.002 P=0.001) 2. The grade of stomatitis (mean of total score) for patients in the experimental group B were significantly lower than in the experimental group A (F=1.96 P=0.0024). 3. In incidence of tougue change, control group, experimental group B were significantly higher than experimental group B(F=6.84 P=0.0039). 4. In control group and experimental group A, oral infection due to pathogenic bacteria were identified. In conclusion, mouth care with nystatine solution four times a day could reduce the incidence of stomatitis and secondary oral infection due to stomatitis. Thus active mouth care protocol which used to nystatine solution gargling need to prevention of stomatitis in chemotherapy patients.