Background and Objective: Organ donation following brain death is an important way to provide organs for transplantation. This study was conducted in order to identify the obstacles in the organ donation process following brain death in the transplant center of northern Iran. Materials & Methods: This cross sectional study was conducted on 195 patients with brain death admitted to educational and medical hospitals of Guilan University of Medical Sciences between March 20, 2021 and March 20, 2023. Based on the research criteria, the patients were divided into two groups suitable and unsuitable for organ donation. From the patient’s files, information related to age, gender, underlying disease, smoking, level of education, the cause of brain death and in case of non-consent to donation, the reasons of family refusal of organ donation was extracted and recorded in the data collection form. Finally, the results were compared between the two groups. The recorded data was analyzed in SPSS software, version 21. The significance level was considered less than 0.05. Results: In our study, the majority of patients were men with a number of 137 (70.30%) and an average age of 51.8 ± 20.92. The main cause of brain death in two groups suitable and unsuitable for donation was traumatic and cerebro vascular events, respectively (P = 0.0001). Also, there was a statistically significant difference between the two groups in terms of age (P = 0.0001), level of education (P = 0.0001), history of smoking (P = 0.0001) and underlying disease (P = 0.0001). The refusal rate of families to donate organ was 31% that the most important reason was not accepting brain death as the cause of death. The results of the study showed that after the inappropriateness of the conditions of brain dead patients and their organs for donation, the family, lack of consent is the most important factor that leads to organ donation failure. Although, in the investigation of the relationship between the factors of age (P = 0.380), gender (P = 0.304), level of education (P = 0.160), marriage (P = 0.060) and ethnicity (0.975) with consent to donation by relatives, no significant relationship was observed. Conclusion: The results of the study showed that after the inappropriateness of the conditions of brain dead patients and their organs for donation, the family, lack of consent is the most important factor that leads to organ donation failure. Also, there are several factors that prevent the relatives of brain dead patients from organ donation, the most important of which is the lack of sufficient information on brain death and the organ donation process and the lack of appropriate educational interventions in this field.