The present application discloses a device and method for detecting and ablating hydrates in a natural gas pipeline. The device includes a transmission mechanism, a detection mechanism and an ablation mechanism. The detection mechanism and the ablation mechanism are both connected to the transmission mechanism through an elastic connector, such that the device can smoothly pass through bends in the natural gas pipeline. The transmission mechanism includes a universal wheel component, which forms static friction with an outer wall of an inner natural gas pipeline, such that the device can move along the inner natural gas pipeline. The detection mechanism detects the temperature of the natural gas pipeline and determines whether hydrates are generated in the natural gas pipeline to block the pipeline, and then the blockage is heated by the ablation mechanism to ablate the hydrates.