 This paper provides a comprehensive review on the nanotechnology application in the petroleum industry, including the exploration, drilling, completion, production, and enhanced oil recovery, EOAR, processes. The performance of nanoparticles in EOAR is analyzed, and tips on improving the performance of nanomaterials are given. The future research directions for nano-EOAR are also identified. This article was authored by Madhan Nurajista, Koengwa, and Jishi Nyu.