The invention discloses a stepped collision avoiding isolation zone device which is characterized by comprising a metal baseplate and two columns of outer guardrail combinations, wherein two sides of the metal baseplate are inwards-concave cambered surfaces, middle vertical plates are arranged in parallel between the two columns of outer guardrail combinations and are welded in the middle of the metal baseplate, and a stripped water channel is placed between each middle vertical plate and each outer guardrail combination; each stripped water channel is internally provided with partition plates at equal distance and is partitioned into at least two water tanks by the partition plates; ports of the adjacent water tanks are flush, and the bottoms of the water tanks are sequentially lowered in a stepped form; and through holes are formed in the left and right side walls of the water tanks. The stepped collision avoiding isolation zone device has the beneficial effects that the stepped collision avoiding isolation zone device is provided, water in the adjacent water tanks can flow to form flowing water, so that the problem that dead water in the existing water tanks is easily rotted and easily becomes smelly is effectively avoided, and the manual maintaining cost is reduced.