The utility model provides a take road maintenance car of lift warning light, including the automobile body, set up a warning light operating system on the automobile body, warning light operating system includes obstacle detection module, control module, lift drive module, power module. The obstacle detection module is used for monitoring vehicle advancing direction's barrier and producing signals, and control module is used for handling the signal of obstacle detection module transmission and produces the instruction of controlling lift drive module, and lift drive module drives the warning light under the drive of control module instruction, and power module is used for providing operating voltage. The utility model discloses stretch height to roof top at the in -process of advancing with the warning light, can in time withdraw to the automobile body rear when meeting the limit for height obstacle.