Hemorrhagic fever with renal syndrome (HFRS) is a zoonotic infectious disease caused by Hantaviruses, a group of RNA viruses belonging to the Bunyaviridae family. Humans may get the disease by contamination with excreta of carrier rodents. The disease typically manifests with the triad fever-thrombocytopenia-acute kidney injury (AKI). Although its global prevalence seems to be increasing, Hantavirus infection is still commonly overlooked, because of its clinical polymorphism and non-specific symptoms, particularly in mild cases. Until recently, the disease was virtually unknown in Romania, due to lack of physicians' awareness and of adequate laboratory diagnostic techniques. In this article, we present the first six cases of HFRS diagnosed in our country, based on serology testing. We review the existing literature on HFRS and discuss our findings in comparison with other reports. All our patients presented with fever, flu syndrome, bleeding, gastrointestinal symptoms, and oliguria. Among laboratory abnormalities, elevated serum creatinine and liver enzymes, high C-reactive protein, leukocytosis, low platelet count, and hematuria were constantly seen. Five patients required hemodialysis. All patients survived and five of them completely recovered their renal function, while only one patient retained a mild impairment of the glomerular filtration rate. From a clinical viewpoint, we believe that Hantavirus infection should be considered in all patients presenting with fever, thrombocytopenia, and AKI, when specific serology testing would be indicated. From a public health perspective, we suggest that future efforts in our country should be directed toward (1) increasing the understanding and the awareness of this disease among health care professionals, (2) educating the population at risk on the application of prophylactic measures, (3) expanding the availability of diagnostic laboratory tools, and (4) developing research on national zoonotic virus reservoirs.