Allogeneic SCT is a therapeutic method that provides the possibility of curing many malignant and non-malignant hematological diseases, and today it has increasing power in the treatment of congenital immunodeficiencies, genetically conditioned autoimmune and metabolic diseases and other diseases. The aim of this retrospective study was to evaluate the effectiveness of allogeneic SCT in the treatment of our population of 306 patients with refractory and relapsed hematological diseases, who were transplanted at the UHC Zagreb in the period between 19.01.2011. and 19.12.2017, according to the parameters like overall survival, acute and chronic GvHD and relapse of the disease. The results showed that allogeneic SCT is very useful in the treatment of our patients; the overall survival of all 306 patients at 42 months post-transplantation was 52%. Overall survival at 42 months post-transplantation was best in the group of patients with CML and HL; 71% and 76%. The group of patients with MDS and myelofibrosis had an overall survival at 42 months post-transplantation of 56%, whereas the group of patients with acute leukemias had overall survival of 52% at 42 months post-transplantation. Overall survival of patients with refractory and relapsing acute leukemias at 36 months post-allogeneic SCT was 31%, whereas patients with NHL at 24 months post-transplantation had overall survival of 29%. The incidence of acute GvHD was the highest in the NHL group and was 58%. Chronic GvHD was most commonly diagnosed in the group of patients with myelofibrosis; in 57% of them. Relapse of the disease was most common in the group of patients with HL; in 36% of them. Our data show that allogeneic SCT is an useful method of treating refractory hematological diseases, but, with the development of new drugs and new approaches to the transplantation, there is still room for improvement.