Objective To analyze the main factors affecting early using enteral nutrition and the effect of enteral nutrition within 72 h after burning on outcomes by presenting a retrospective cohort study of 11 years of hospitalization data, to provide evidence for enteral nutrition regimens for severe burn patients. Methods A retrospective study analyzed adult extensive burn patients between January 2009 and December 2020. Patients enrolled in this study who admitted to the burn department within 24 h after burning and with a burned area of more than 30%. Univariate and multiple regression were used to analyze the main factors affecting early using enteral nutrition in patients with severe burn. Non parametric Mann-Whitney U test was used to compare the main influencing factors of enteral nutrition implementation within or after 72 h, as well as the impact on the treatment outcomes such as 28-day survival rate and in hospital survival rate. Results The univariate analysis found that total burn area, full-thickness burn area, burn type, and inhalation injury were the main factors of the time to initation of enteral nutrition in patients with severe burn (P<0.05). Incorporating the above single factors into multiple regression analysis, we found that the main factors affecting enteral nutrition using in patients with severe burn were full-thickness burn area (P=0.017) and inhalation injury (P=0.001). To analysis whether enteral nutrition was started within 72 h after burning, we found that inhalation injury and larger area of full-thickness burn area in patients was the main factors for initiating enteral nutrition. After matching injury situation with pre-injury situation, we found that using enteral nutrition within or after 72 h after injury were no significant differences in the survival rate, 28-day survival rate, and positive blood culture rate （P>0.05），but was associated with the lower incidence of bacteria positive in intravenous catheters (P=0.001) and the lower rate of parenteral nutrition treatment used within 7 d after burning (P=0.001). Conclusions The main factor for influencing early implement enteral nutrition in patients with severe burn were large area of full-thickness burn and inhalation injury. Enteral nutrition using within 72 h after burning reduces the incidence of catheter infection and the use of parenteral nutrition, thereby reducing the risk of treatment in patients with severe burn.