An antijamming chaotic lidar system with high resolution for automotive collision warning radar application is proposed. Utilizing the broad bandwidth chaotic light emitted from a laser diode with optical feedback as the probe beam, we can locate the target by the correlation characteristics of chaotic light. Further, the velocity can be obtained by time differential method. Experimental results show this real-time chaotic lidar can obtain sub-second measurement period and 9 cm range resolution. Simulative results show that, as automotive collision warning radar, the chaotic lidar has good antijamming capability, can resolve the false alarm problem resulting by the multi-channel and noise jamming.