In the presented case, clipping of aneurysm of the anterior cerebral artery (A CeA) and the anterior communicating artery (ACoA) in acute subarachnoidal hemorrhage (SAH) was complicated by the development of vasospasm and transient diabetes insipidus (DI). The cause of DI was ischemia of the anterior portions of the hypothalamus due to ACeA and ACoA spasm. The use of the standard triple H-therapy protocol in the presence of DI failed to achieve the optimal parameters of hemodynamics and cerebral perfusion pressure due to the development of severe polyuria. Addition of the standard triple H-therapy protocol by hormonal replacement therapy with desmopressin could yield adequate systemic hemodynamic parameters. During this treatment, the state became stable and vasospasm regressed. The manifestations of DI ceased with the values of cerebral circulation being normal.