As a multi-dimensional concept, empathy suffers from vague and inconsistent definitions which makes it difficult to compare results between studies and advance knowledge about empathic abilities and experiences. Most commonly, empathy involves an aspect of cognition, emotional sharing, and distinction between the self and the other. The Late positive potential (LPP) is an emotion-sensitive event-related potential (ERP) that is increasingly used to study empathic abilities. As one of the later components it has shown robust sensitivity to emotional stimuli compared to neutral and is often associated with cognitive processing of emotions. In this review, a total of n = 30 ERP studies was investigated in order to investigate how the concept of empathy is studied in terms of conceptual definition, task operationalisation, and relation to the LPP. Results in the studies mainly confirm the emotion effect on LPP and a tendency for enhanced LPP in conditions of self-focus. Conceptualisations of empathy are multifaceted and the LPP is predominantly interpreted as a marker for cognitive processing of emotional content in empathic responding. However, there is still no clear picture about the specifics of these underlying cognitive modulations.