To keep up with technological advances and macro-economic trends, higher education has increasingly focused on developing students' employability competences through mentoring programs. However, measuring the effectiveness of such mentoring programs has remained difficult, because many mentoring measurements are not validated or grounded in theory. Furthermore, existing questionnaires have mostly focused on one or two types of support, ignoring the wide variety of support types offered by a mentor. Therefore, the current study's aim was to develop and validate a new questionnaire measuring various types of mentoring support. Based on a systematic literature review, a 35-item questionnaire was developed and data were collected from mentoring programs at four higher education institutions. Data were analyzed through exploratory factor analysis (n = 225), confirmatory factor analysis (n = 208), and cross-validation (n = 101). The results support a 6-factor model (21 items) that is statistically valid and reliable for use in universities (of applied sciences). The model includes the following factors, referring to types of support and their features: trust and availability, emotional support, networking support, autonomy support, similarity, and empathy. This questionnaire makes an original contribution insofar as (1) it is based on a sound, theoretical framework, and (2) it was demonstrated to be valid and reliable across different sub-populations in higher education. The questionnaire provides educational practitioners with a sound and valid tool to evaluate the quality of their mentoring program. It can also be used to assess what types of support could be offered to a greater extent.