Wettability is one of the most important factors affecting micro-distribution of water and oil in rock pore space, capillary pressure, relative permeability, and irreducible water saturation. Wettability measurement is one of key research branches in special core analysis. It is very useful to develop the best development strategy and select an optimal EOR method on the basis of accurate known wettability of target petroleum reservoir. The three classical wettability evaluation methods and their disadvantages are briefly introduced. The development history, research results, and applications are reviewed through the investigation into a large number of professional literatures. Meanwhile, the basic mechanism, accuracy, and advantages are also analyzed with the multiphase fluid flow theory in wettability evaluation using Nuclear Magnetic Resonance (NMR).