Collision prevention support device

PROBLEM TO BE SOLVED: To provide a collision prevention support device deciding a risk of collision with vehicles around and making a proper response at a proper timing, irrespective of whether road information such as a lane marker on the road can be detected or not. SOLUTION: This traveling support device has: a first sensor detecting a surrounding vehicle running around its own vehicle; a second sensor detecting a lane marker on the road; a first calculation part calculating positional relation between the own vehicle and the surrounding vehicle; a second calculation part calculating a risk degree showing a distribution of probability that the surrounding vehicle collides with the own vehicle based on the positional relation; a setting part setting a control threshold value based on the risk degree; and a setting part setting the control threshold value based on the positional relation between the own vehicle and the surrounding vehicle when the second sensor does not detect the lane marker, and setting the control threshold value based on the lane marker and the positional relation when the second sensor detects the lane marker. COPYRIGHT: (C)2010,JPO&INPIT