Objective: To explore the clinical significance of circulating DNA in diagnosis of acid and alkaline chemical burn. Methods: Sixty-one patients burned by acid or alkaline, including 30 cases of acid burn and 31 cases of alkaline burn, were randomly collected from June 2014 to April 2018 in Second People’s Hospital of Yichang. The clinicopathological data were collected, and the circulating DNA levels and blood routine indexes were measured respectively on Day 1, 5, 10, 15, 30 and 60 after burn. Results: The circulating DNA level was higher than normal level (25 ng/mL) on the 1st day after burn (25 ng/mL). On the 5th day after burn, the circulating DNA level reached the peak, and the acid and alkaline burns were (245.38±56.47) and (402.89±85.56) ng/mL, respectively. Then, the circulating DNA level of the patients showed a downward trend, and on the 60th day after burn, the plasma circulating DNA level was close to the normal level. The circulating DNA level was no significant relationship with the age, sex ratio, burn site, white blood cell number and the absolute value of monocytes (P>0.05); while, positive relationship with the burn area, interval between burn and hospital treatment, burn index, deep II degree burn area, III degree burn area, self-rescue before admission, hematocrit, hemoglobin and peroxidase activity (P<0.05); however, negative relationship with shallow II degree burn area (P<0.05). In addition, the circulating DNA level was significantly positively correlated with RBC count in patients with alkaline burns (P<0.05), while, circulating DNA level was not correlated with RBC count in patients with acid burn (P>0.05). Conclusion: The circulating DNA level can be used in progression evaluation of acid and alkaline chemical burn, as well as used as a diagnosis parameter in treatment of acid and alkaline chemical burnt patients.