Aim The aims of the study were to assess the psychological impact of SARS bio-disaster on healthcare workers. Methods The participants were 127 healthcare workers who had taken care of suspected SARS patients. All participants completed the Chinese Health Questionnaire (CHQ), Eysenck Personality Questionnaire, and Parental Bonding Instrument at the first stage and the CHQ again a year later. Results Healthcare workers that had mental symptoms at follow-up reported the symptoms were associated with daily-life stress and not the SARS crisis. The physicians had more somatic symptoms than nurses, suggesting different professions have different impact on mental health. Additionally, individual's early maternal attachment and neuroticism were found to have greater effect on mental health of life-threatening stress. Conclusions Life-threatening and daily-life stress show two different patterns of influence on mental health. These results provided a preclinical model for understanding, and preventing, human stress-related psychiatric disorders in the future.