In　order　to　realize　the　ranging　function　of　the　vehicle　monocular　camera　on　unstructured　roads,　it　is　proposed　to　use　the　method　based　on　texture　features　and　soft　voting　to　detect　the　vanishing　point　of　the　road　and　the　road　edge,　and　use　camera　calibration　method　and　tri-linear　method　to　obtain　the　internal　and　external　parameters　of　the　camera.　Obtain　the　distance　information　in　the　image　according　to　the　geometric　relationship　model.　Experiments　show　that　this　method　can　measure　the　distance　of　an　unstructured　road　image　with　only　the　centerline　of　the　road　relying　only　on　the　vehicle　monocular　camera.　The　method　has　a　wider　application　range　and　is　simpler　in　actual　engineering.　©　2020　Institute　of　Physics　Publishing.　All　rights　reserved.