A driving position adjusting system automatically adjusts a driving position in a second vehicle appropriately to a target user based on a driving position in a first vehicle adjusted by the target user. The driving position adjusting system includes a storage device, a detection device, an estimation device, a transmission device, and a control device. The storage device stores statistic data. The detection device detects a selected one of a plurality of divided range segments of the driving position in the first vehicle, the selected one being selected by the target user. The estimation device estimates an optimum one of the plurality of divided range segments in the second vehicle based on the statistic data and the selected one. The transmission device transmits to the second vehicle the optimum one in the second vehicle. The control device controls the driving position in the second vehicle correspondingly to the optimum one.