Unlike most electrical systems, electrical submersible pump (ESP) system grounding has its unique feature: it must be divided into two zones, i.e., surface and downhole zones, grounding practices for the two zones are significantly different. In this paper, the current practice and future trend for ESP system grounding is presented, which is based on an extensive literature review, including the industry practice, published technical papers, and the patent search. This paper will be extremely useful for field engineers and ESP system design engineers to understand requirements, techniques, and future development directions for ESP system grounding.