Higher education institutions face the challenge to promote diversity competence. We suggest a procedure which can help raise awareness for diversity issues amongst staff and students and thereby foster diversity competence and facilitate the implementation of diversity strategies within higher education institutions: to include a self-assessment tool regarding diversity competence in the regular teaching evaluation. In this research we complemented a well-established course evaluation tool that is widely used in Germany, the HEsaCom, by a new subscale measuring subjective gains in diversity competence. As part of regular teaching evaluations, 8700 questionnaires comprising the HEsaCom-scales and the new scale on diversity competence were collected in 1396 different seminars of a large university in Germany. Results show good reliabilities for all scales. From factor analysis, the new scale emerged as an additional subscale of the HEsaCom, with the established factor structure remaining unchanged. Students attending a cross-study course in which diversity had been a topic and students attending courses in which no participant had experienced social discrimination reported significantly higher diversity competence gains than students from the remaining courses. We discuss how higher education institutions can apply the questionnaire used in our study for their diversity management.