Post Translational Modification (PTM) is a process in which covalent addition of functional groups on protein occurs to maintain their structure, function and stability. Every PTM process in our living system occurs to enhance the functional diversity of a protein. But sometimes, it occurs without any regulation and that might lead to autoimmunity. Rheumatoid arthritis (RA) is one such chronic, inflammatory, autoimmune disease that affects the joints. Proper treatment can make the symptoms manageable for RA, but it is not curable. Delayed diagnosis of RA can cause severe bone pain, stiffness, inflammation, redness in joints and affect other parts of the body such as the liver, kidney, etc. Early diagnosis of RA is necessary to manage the aggressive symptoms. Currently, Rheumatoid factor (RF) and anti-citrullinated cyclic peptide (Anti-CCP) are considered as biomarkers to diagnose RA. Besides citrullination, several other PTMs are also involved in the generation of autoantibodies, such as carbamylation, glycosylation, glycation, acetylation, ubiquitination, proteolysis, phosphorylation, and lipidation. The aim of this review is to elucidate several changes in the form, nature, and function of PTMs in RA. This review will give a recent overview on the role of PTMs in the pathogenesis of RA with a focus on the post-translational modifications.