Background: Leaving against medical advice (LAMA) can be defined broadly as a patient's insistence upon leaving the hospital against the treating team has expressed advice, which is both a challenge and concern for physicians, as these patients lost to follow-up, and their outcomes remain unknown. There is no previous study conducted to find the prevalence and causes of LAMA in brain tumors patients in the Middle East to the best of our knowledge. Methods: Patients studied in this research are those who were diagnosed with any type of brain tumors and were admitted to the Neurosurgical Department in Khoula Hospital (KH) but signed LAMA in the two years between January 2017 to December 2018 by going through the electronic medical records. Data obtained from the health information system includes socioeconomic characteristics, health status-related data, diagnosis-related data, and the reasons for LAMA. Results: A total number of 302 patients with brain tumors included in this study. Twenty-eight patients (9.2%) signed LAMA with a majority of those who signed LAMA were in the young adult's group (3-39 years) and represented 18 (64%). Eight patients (28.57%) among the LAMA group and 43 patients (15.69%) in the non-LAMA group have tumors in the frontal lobe, which has found to be the most familiar location (29%). There was a significant relationship between the reason for LAMA and gender (P = 0.020). Conclusion: Younger patients, male, Omani, newly diagnosed tumors, and tumors in the frontal lobe were all risk factors for LAMA. Education and awareness about LAMA recommended in order to avoid readmission and loss of follow up.