The purpose of this research is to establish an overall data set associated with the VOI (Volume of Interest), which is available for simultaneous assessment of PET/MRI and PET/CT regardless of the use of contrast media. The participants as objects of this investigation are 26 healthy examinees in Korea, SUV (standardized-uptake-value)s-maximum evaluation for whole-body F-18 FDG (fluorodeoxyglucose) PET/MRI image using VOI of normal region has exhibited very significant difference to that for whole-body F-18 FDG PET/CT image (significant probability value (P) < 0.0001). However, there appeared high correlation between them in view of statistics (R-square (R) > 0.8). It is shown that one needs to decide SUVs-maximum for PET/MRI with the reduction of 25.0~26.4% from their evaluated value and needs to decide with the reduction of 28.8~29.4% in the same situation but with the use of contrast media. The use of SUVLBM-maximum (SUVLean Body Mass-maximum) is very advantageous in reading overall image of PET/CT and PET/MRI to medical doctors and researchers, if we consider its convenience and efficiency. We expect that this research enhances the level of the early stage accurate diagnosis with whole-body images of PET/MRI and PET/CT.