Driver mental status plays a crucial role in ensuring road safety and factors such as fatigue, stress, and lack of attention significantly increase the risk of accidents. Conventional monitoring systems often rely on single indicators, which may not provide a comprehensive evaluation of driver condition. In this study, we propose a Fuzzy Logic (FL) based system for assessing driver condition by integrating multiple parameters, including physical parameters for deciding Driver Body Condition (DBC). We call this system FL-based DBC (FLDBC) system. As input parameters for FLDBC system we consider Pupil Dilation (PD), Driver Facial Expression Changes (DFEC), Handle Reaction Time (HRT) and Driver Heart Rate Status (DHRS). The output parameter is DCB. We evaluated the implemented system by computer simulations. The simulation results show that DCB is good when the pupil dilation is normal. With increasing HRT, the DCB value increased. Also, when DFEC and HRT changed, the DCB value increased.