Abstract: On 4 May 2020, an extraordinary supercell thunderstorm event occurred in eastern Guizhou, China, the hailstorm lasted for more than 6 hours, the layered characteristics of the supercell echo of the hailstorm was analyzed. The results show that: (1) The hailstorm cell developed from a block echo to a hook echo, moving from east by north to east by south, with a moving speed of 50 km·h⁻¹, and the maximum echo intensity reached 71.5 dBZ, with the maximum echo heights of 45 dBZ and 55 dBZ reaching 15.2 km and 12.1km respectively. (2) The concentrated period of hailfall and occurrence of large hail were closely related to the height of the 45 dBZ and 55 dBZ extending to the height of −20 ℃ layer. The occurrence time of large hail was consistent with the concentration period when the 55 dBZ echo height was greater than the height of −20 ℃ layer. (3) The Vertically Integrated Liquid (VIL) values consistently remained in the high value area above 45 kg·m⁻². The probability of hail (POSH) was 100%, but there was a significant difference between the maximum expected hail size (MEHS) and the observed ground hail size. (4) The high-altitude wind of hailstorm cell changed from southwesterly wind to northwesterly wind with the increase of height. The leading edge of the high-altitude wind displayed a strong radial velocity gradient band, with a maximum average radial velocity reaching 19 m·s⁻¹. In the core of the intense echoes, the positive and negative radial velocity blocks and maximum velocity ambiguity appeared, and the convergent feature of negative radial velocity zone in the shape of an arch was observed on the north and south sides. The strong converging updrafts favored the formation, maintenance, and growth of large hail. (5) The area with the echo intensity ≥ 45 dBZ in the concentrated hail area corresponded to the actual affected area of hail. The main concentration of hail occurred in the area with the echo intensity ≥ 55 dBZ. The duration of the echo intensity ≥ 45 dBZ corresponding to single staion hailfall was consistent with the actual starting and endimg time of the hail.