Alarming apparatus and method for automotive vehicle

A vehicular running state and a frictional coefficient ( mu x) of a road surface on which the vehicle is running are detected. A vehicle using road surface frictional coefficient ( mu car), which corresponds to the road surface frictional force the presently running vehicle is using, is calculated on the basis of the detected vehicular running state. A road surface frictional coefficient utilization rate (R mu ) is calculated, which is the ratio of the calculated vehicle using road surface frictional coefficient ( mu car) to a maximum frictional coefficient detected by a road surface frictional coefficient detector. An alarm controlling section outputs an alarm command to an alarm device to issue an alarm when the calculated road surface frictional coefficient utilization rate (R mu ) is equal to or larger than a set value.