A longstanding objection to moral realism is epistemological: there seems to be no viable account of our epistemic access to putative moral facts. In response to this objection, a number of moral realists have recently defended moral empiricism. On this view, we acquire moral knowledge by perceiving moral facts via our ordinary sensory organs. I argue that we should reject moral empiricism. The central problem is that moral empiricists are compelled to accept a model of moral perception that presupposes that epistemic agents already have prior, non-perceptual epistemic access to the moral facts. I consider four responses to this problem available to moral empiricists. (The first three have been actually advanced. The fourth is a potential reply.) I argue that these responses fail. I conclude that moral empiricism does not supply us with a satisfying account of how it is that human beings have epistemic access to the putative moral facts posited by moral realists.