Although some studies have found that guilt may precede, motivate, or be a consequence of obsessive–compulsive disorder (OCD), the relationship between guilt and OCD has been under investigated. The studies that explored the role of trait guilt (guilt propensity) in OCD reported inconsistent findings and failed to support its predictive role. Since it has been suggested that OCD patients perceive guilt in a more threatening manner, it might also be relevant to test to what extent they negatively evaluate the experience of guilt (i.e., guilt sensitivity; GS). Study 1 investigated the psychometric properties of a new 10‐item Italian measure developed to assess GS—named Guilt Sensitivity Questionnaire—in a nonclinical sample (N = 473). Results from exploratory factor analyses supported the unidimensionality of the scale. It also showed excellent internal consistency and good discriminant validity. Study 2 investigated the role of GS in OCD symptoms, in particular with regard to responsibility for harm obsessions and checking compulsions, using a heterogeneous OCD sample (N = 61) and a control group of patients with anxiety disorders (N = 47). GS was the unique significant predictor of checking related OCD symptoms independent of negative mood states and obsessive beliefs. Guilt Sensitivity Questionnaire scores of patients with responsibility for harm concerns were significantly higher than those of patients with other kinds of obsessive concerns and with anxiety disorders. Findings supported the hypothesis that GS plays a relevant role in OCD symptoms when checking rituals are primarily involved. Implications for current cognitive behavioral models are discussed. Key practitioner message: Guilt sensitivity may play a role in checking‐related OCD symptoms. We developed a psychometrically sound unidimensional 10‐item scale to assess guilt sensitivity. Guilt sensitivity was a unique predictor of checking‐related OCD symptoms. Targeting beliefs about the intolerability/dangerousness of experiencing guilt may be useful. Acceptance‐based approaches may be helpful as they promote the acceptance of guilt.