Previous research has shown that intrusions are part of the psychopathology of mental disorders. Imagery techniques seem to be an effective treatment of negative intrusions. Since negative mental imagery is part of health anxiety, the present study investigated the impact of imagery techniques on health anxiety. A total of 159 students with elevated scores in a health anxiety questionnaire watched an aversive film concerning a cancer patient and were randomly allocated to one of three interventions (positive imagery, imagery reexperiencing, imagery rescripting) or the control group. The intervention lasted 9 min. Physiological data (heart rate and cortisol) as well as psychological measures, such as mood ratings, health anxiety scores, and intrusions, were assessed during the appointment, while psychological measures were assessed over a period of 1 week after the intervention. Cortisol levels changed over time depending on the intervention. Heart rate changed during the 9‐min interventions as well, with the fastest decrease during imagery rescripting. Moreover, negative mood and distress decreased after the intervention, while intrusions were reduced 1 week after the intervention in all groups equally. The results suggest that imagery rescripting is a promising technique that seems to activate a process of deep elaboration. Therefore, it might be an adequate way to target health anxiety symptoms such as anxiety, intrusions, and avoidance or safety‐seeking behavior. Further studies should focus on imagery rescripting in clinical samples with health anxiety and target individual intrusive images to increase effectiveness. Nevertheless, the development of a long‐term explanatory model of rescripting is needed.