Recent research has begun to explore the experiences of Christian undergraduates and faculty in biology to illuminate reasons for their underrepresentation. In this study, we focused on the experiences of graduate students and explored Christianity as a concealable stigmatized identity (CSI) in the biology community. We constructed interview questions using this CSI framework, which originates in social psychology, to research the experiences of those with stigmatized identities that could be hidden. We analyzed interviews from 33 Christian graduate students who were enrolled in biology programs and found that many Christian graduate students believe the biology community holds strong negative stereotypes against Christians and worry those negative stereotypes will be applied to them as individuals. We found that students conceal their Christian identities to avoid negative stereotypes and reveal their identities to counteract negative stereotypes. Despite these experiences, students recognize their value as boundary spanners between the majority secular scientific community and majority Christian public. Finally, we found that Christian students report that other identities they have, including ethnicity, gender, nationality, and LGBTQ+ identities, can either increase or decrease the relevance of their Christian identities within the biology community.