Self-criticism is a stable personality trait identified as a serious risk factor for psychopathology and weight-related health problems. Therefore, it is relevant to epidemiological research, which requires a relatively brief instrument for measuring trait self-criticism in the general population. The current study introduces a brief measure of self-criticism and presents empirical results that inform on its reliability and validity. Based on the six-item version of the Depressive Experiences Questionnaire Self-Criticism (DEQ-SC6), thorough psychometric analyses on a German representative sample (N = 2,516) were conducted and resulted in the final four-item scale: the Depressive Experiences Questionnaire Self-Criticism 4 (DEQ-SC4). Its internal consistency was good and a one-dimensional factor structure showed a good model fit. In terms of construct validity, the DEQ-SC4 was moderately linked to symptoms of depression and a non-linear association between the DEQ-SC4 and body mass index was observed, with the highest levels of self-criticism reported by underweight participants. In addition, the DEQ-SC4 showed high positive correlations with another short version of the DEQ-SC and the Big Five personality dimensions assessed in samples of university students (N = 206) and patients (N = 55), meeting theoretically-based expectations. The DEQ-SC4 therefore represents a brief screening measure of self-criticism in the general population with good psychometric properties.