Performance boost of the Polymer Electrolyte Membrane Fuel Cell can fundamentally be achieved by increasing catalyst surface area while reducing particle size, decreasing the ionomer thickness and replacing platinum with an highly effective catalyst. Each of the above aspects are the sources for PEMFC modelling. This article is provided concise overview of PEMFC catalyst models based on quantum mechanics, statistical mechanics and computational fluid dynamic methods. The principles of modelling techniques are briefly described under four categories namely Density Functional Theory, Reactive Force Field-ReaxFF & other widely used Semi-empirical methods, Computational Fluid Dynamics and Coarse-grained methods. Then, oxygen reduction reaction models, hydrogen oxidation models and solvation effects for the above reactions are surveyed. Coarse graining methods are discussed using selected literature as a means of relating atomistically obtained information to mesoscopic systems and contributions from ReaxFF as reaction modelling technique using atomistic parameters are also explored. Several instances of the application of atomistic modelling to platinum, platinum-alloys, coarse graining methods to platinum-carbon-ionomer system and force field methods to carbon atom platelets with platinum-clusters are reviewed in detail. Limitations of the computational fluid dynamic techniques used in mesoscopic continuum models such as semi-empirical and mechanistic models are mentioned. Last but not least the possibilities for future catalyst modelling are presented.