1. A road image analyzing apparatus, comprising: two image pickup units that photograph the same position from different directions; a continuous component extracting unit that extracts a linear component through analysis on an edge component extracted from image data obtained by one of the image pickup units, extracts a columnar structure, a road marking, and a guardrail as the continuous component that are repetitively present in a predetermined direction or continuous in the predetermined direction in an image on the basis of a position and an inclination of the linear component and association between linear lines including data on a width of a road marker and a width between road markers, and excludes the columnar structure from the continuous component, on the basis of the inclination or the position on a road of the linear component; a three-dimensional position calculating unit that combines an end point of the continuous component with the columnar structure excluded and image data obtained by the other image pickup unit to calculate three-dimensional position information of the continuous component; and an identifying unit that determines whether the continuous component is a road marking or a guardrail on the basis of the three-dimensional position information calculated by the three-dimensional position calculating unit.