Objective To explore the effect of out-hospital continuous nursing combined with in-hospital psychological guidance on traumatic stress in severe burn patients．Methods A total of 86 patients with severe burn treated in the Affiliated Hospital of Nankai University（Tianjin Fourth Hospital）from June 2020 to June 2022 were selected as the research objects．The patients were divided into observation group and control group by random number table method,with 43 cases in each group．The control group received routine care,and the observation group was supplemented with out-hospital continuous nursing and in-hospital psychological guidance on the basis of routine care．The traumatic stress indexes [serum tumor necrosis factor-α（TNF-α）,interleukin-6（IL-6）,β-endorphin（β-ep）],psychological toughness,coping behavior and post-traumatic growth level of the patients were evaluated．The correlation between traumatic stress and mental toughness was analyzed．Results Before intervention,the levels of TNF-α,IL-6 and β-ep were not significantly different between the two groups（P>0.05）．After intervention,the levels of traumatic stress-related indicators were decreased between the two groups,and the reduction was greater in the observation group（P<0.05）．After intervention,C-PTGI scores related to optimism,strength and fortitude were increased in both groups,which were higher in observation group（P<0.05）．Pearson correlation analysis showed that the levels of TNF-α,IL-6,β-ep and other traumatic stress indexes were significantly negatively correlated with the levels of mental toughness（P<0.05）．After intervention,the positive coping TCSQ scores of both groups were increased,the observation group was higher,and the negative coping scores were decreased,while the observation group was lower（P<0.05）．After the intervention,the scores of interpersonal relationships,mental changes,life appreciation,personal strength,and new possibly relevant C-PTGI score subscale were increased in both groups,and higher in the observation group（P<0.05）．Conclusions The combination of out-hospital continuous nursing and in-hospital psychological guidance for severe burn patients can reduce the level of post-traumatic stress and negative response score of patients,and improve the level of mental toughness,post-traumatic growth and positive score of patients,and the level of post-traumatic stress is significantly negatively correlated with the level of mental toughness．