Objective: To probe into the status characteristics and the dynamic change trend of the psychological stress among medical staff at four time points after exposed to blood-borne pathogen. Methods: A longitudinal study was carried out among 78 medical personnel in this study, with 67 of hepatitis B vims, 5 of hepatitis C virus, 4 of HIV and 2 of treponema pallidum respectively. Perceived stress scale (PSS-4), Post-traumatic stress disorder Checklist-5 (PCL-5), Hospital anxiety and depression scale (HADS) were used to assess the psychological status, including perceived stress, post-traumatic stress symptom, anxiety and depression at the four times. Data analysis was performed using repeated measures analysis of variance (RMANOVA) and paired sample t test to explore time effect of the psychological stress reaction in the exposed population. Results: The scores of PSS-4, PCL-5, HADS- A, and HADS-D increased from exposure, and gained highest at one month after exposed, then gradually declined with time <0. 05). Conclusion: It suggests that the levels of perceived stress, post-traumatic stress symptom, anxiety, depression may be the highest at one month after exposed. [ABSTRACT FROM AUTHOR]