The present study examined the relationship of cognitive and emotional representations of illness specified by self-regulation theory on emotional responses of patients with abnormal screening results. Participants were 660 women who received an abnormal cervical smear and 701 men and women who received an abnormal colorectal cancer screening result. Participants completed postal questionnaires containing measures of illness representations and specific emotions. Factor analyses of cause components produced three factors for each sample, corresponding to psychological stress, biological, and behavioural causes. Regression analyses showed that, after controlling for demographic variables, perceived consequences, illness identity, and causal attributions to psychological stress explained significant variance in emotion. Emotional representations also accounted for unique variance in emotional responses. Results indicate congruence in the relationships between illness representations of an emotionally salient event and emotion in patients from the two cancer screening programmes and support the internal validity of self-regulation theory.