DRIVING INSTABLITY DETERMINATION DEVICE

The purpose of the invention is to improve the precision in detecting the driving instability. The driving state determination section 120 determines whether the state is a prescribed driving state by determining whether the information of the operation state of the driving operation unit and the vehicle state as the running state data is disturbed. Based on the running state data for detecting the unstable state of the driver, the running state distribution computing section 130 excludes the running state data when the state is determined to be the prescribed driving state, and the running state distribution computing section computes the first and second running state distributions in different time ranges. The driving instability determination section 140 determines the instability of the driving from the difference between the two computed running state distributions.