Background: Myasthenia Gravis (MG) is an autoimmune disease that affects neuromuscular transmission with various clinical manifestations, including muscle weakness and fatigue. Muscle weakness worsens the severity of MG patients and impairs functional ability. Muscle weakness in MG patients that is accompanied by repetitive physical activity causes loss of muscle endurance and affects balance function and movement. Aim: To determine the relationship between disease severity and balance function in patients with Myasthenia Gravis. Methods: This research is a cross sectional study. The Myasthenia Gravis Composite (MGC) scale was used to assess the disease severity of Myasthenia Gravis. One leg stance (OLS) test was used to assess static balance function and the Time Up and Go (TUG) test was used to assess dynamic balance function and functional ability. Rank-Spearman test was used to assess the correlation between disease severity and balance function in patients with Myasthenia Gravis. Results: Thirty-one patients with Myasthenia Gravis were included by consecutive sampling. A significant correlation between disease severity and dynamic balance function was found (p = 0.002; ? = 0.531) with CI 95%. Conclusion: There is a relationship between disease severity and dynamic balance function in patients with Myasthenia Gravis.