The Moral Foundations Theory (MFT) has drawn significant interest from the popular press and academics alike. One of its primary constituting methodologies is the Moral Foundations Questionnaire (MFQ), a self-report instrument aimed to assess the use of five sets of moral intuitions when making moral judgments. The proposed universality and moduliarity of both MFT and MFQ have been challenged conceptually and empirically. We examine the scale’s development and offer a systematic content analysis of 539 scholarly works using the MFQ to estimate its overall reliability. Altogether, 61% of the studies reported Cronbach’s alpha as an indicator for reliability (38% reported no reliability estimate at all). Mean Cronbach’s alpha scores for four of the five subscales were below .70. We discuss implications for the measurement of moral foundations and the evidentiary basis of Moral Foundations Theory.