Research is thought to be a transformative experience in which students gain disciplinary knowledge and skills, become more expert in the practices of science, develop confidence and a sense of belonging in the scientific community, and develop their educational and career plans. Extensive research has shown that mentors play a critical role in this process. However, minimal research has focused on the negative or problematic experiences that students have with their mentors. Prior qualitative work by this research group has identified the range of negative mentoring that undergraduates can experience while doing research. The goal of the current study is to develop and validate a survey measure to quantitatively measure negative mentoring, including its prevalence and impact. This survey will be an important tool that will enable research to explore how negative mentoring impacts undergraduates and allow programs and mentors to evaluate their mentoring quality.