PURPOSE The aim of this study was to identify the effect of dextrose intravenous fluid (IVF) on the blood glucose levels taken from both fingertips of patients with diabetes mellitus (DM) and those without DM. METHODS From October 2012 to February 2013, 21 DM and 25 non-DM patients were recruited. Blood glucose levels taken from the both fingertips of patients at 7AM while IVF was not infusing and at 11AM, 5PM, and 9PM while IVF was infusing. RESULTS The differences between the mean values of blood glucose from the fingertips at four different times was not statistically significant in DM patients as well as non-DM patients. Also intra-class correlation for blood glucose levels from the fingertips with and without IVF infusion in both groups was shown over about 0.95 at each time (p<.001). CONCLUSION Blood glucose levels measured in the same fingertips of both arms were the same regardless of dextrose IVF infusion. The results indicated that IVF with dextrose may not have any significant effect on the fingertip results of blood glucose level. This study may suggest that patients' both arms and any fingertips can be used for blood glucose monitoring even when the patients are on dextrose IVF infusion.