Myasthenia Gravis (MG) patients often report an affected quality of life (QoL). The aim of the current study was to evaluate the QoL of patients with MG in Greece using a specific tool. A cross-sectional online survey was performed. Adult patients were invited to participate. A questionnaire incorporating the MG-QOL15r scale was distributed, following its translation and cultural adaptation into Greek. Overall, 99 valid responses were submitted. The median age (interquartile range) of the participants was 48.50 (13.50) years and 76.80% were females. One third of the patients mentioned that they could not work/changed jobs after their diagnosis (28.30%) and that they face severe restriction of their everyday activities (26.30%). The mean MG-QOL15r score was 13.50 ± 7.70. Patients with important restriction of everyday activities (p < 0.01), patients with more pronounced need of emotional support (p < 0.01), patients with generalized MG (p < 0.01) and patients with myasthenic crises (p < 0.01) reported lower QoL. This study is the first to report on the affected QoL of the Greek population with MG using the MG-QoL15r scale. Further work should be done to incorporate the routine evaluation of QoL in the care of patients with MG.