1. An apparatus for controlling driving of a vehicle based on driver's fatigue, comprising: a first information collector configured to collect biological information of a driver; a second information collector configured to collect road condition information including a road state and a road shape; a route calculator configured to calculate a desired route from a current position of the vehicle to a destination; a fatigue index calculator configured to divide a route on which the vehicle has traveled into a plurality of sections, and to calculate a fatigue index for each section using the biological information, and to correct the fatigue index using the road condition information; a predicted fatigue index calculator configured to calculate a predicted fatigue index corresponding to the desired route using the corrected fatigue index when the desired route is calculated; and a function provider configured to calculate a compensation value according to the predicted fatigue index, and to calculate a final operation value by applying the compensation value to a basic operation value, which is a reference for performing a driver assistance function, and to provide the driver assistance function based on the final operation value to the driver.