Abstract: In the lerge plantations of Eucalyptus globulus Lab. there have been outbreaks of the eucalyptus red leaf dieback on the young trees. The disease seriously threatens the tree preservation and the development of the plantations. This paper presents the preliminary studies on the causal factors and the control of the disease.On the basis of the symptoms observed, the data obtained from a series of tests including screening hopeful materials for combating the disease, effect tests on microelements, and laboratory analysis on the soil and the host tree samples for B content, it can be confirmed that the eucalyptus red leaf dieback is of physiological nature caused by Boron deficiency in the soil. Meanwhile, the preliminary results of the field examplary tests on the effect of applying boran with compound fertilizer appear to be promising.