This article aims to discuss an autoimmune disorder of postsynaptic membrane where auto-antibodies are deposited at neuromuscular junction (NMJ) against ACh receptor (AChR) named MG.Discussing normal neuromuscular transmission .Alongwith (EAMG) Experimental autoimmune myasthenia gravis in which rabbits were immunised with AChR shows an allergic reaction to muscle AChR which usually occurs in MG patients. Furthermore, prognosis of specific antibodies namely AChR-Ab, MuSK-Ab, LRP4-Ab is discuss with clinically recommended tests. And ending with thymoma in MG patients and discussing necessity for thymus imaging of MG patients.