Biological mechanisms of tumor development are largely known, however influence of psychological factors in alcoholics with malignant tumor of the oral cavity and the oropharynx are mostly unexplored. the aim of the research was to examine early family relations and investigate differences in the use of defense mechanisms in alcohol dependent patients suffering from malignant tumor of the oral cavity and oropharynx compared to alcohol dependent persons without malignant tumors and healthy controls. the research included 51 alcohol dependent patients treated for malignant tumor of the oral cavity and oropharynx at the University Hospital Center Rijeka from 2005 to 2009. the control groups corresponded to the experimental group in age, sex and education level. the research used a general demographic questionnaire, the Mini International Neuropsychiatric Interview and the Revised Questionnaire of Life Style and Defense Mechanisms.the research groups showed significant differences in difficult childhood (p < 0.001) including abuse (p = 0.004). the alcohol dependent persons suffering from malignant tumors of the oral cavity and oropharynx significantly less frequently used primitive defense mechanisms of regression (p = 0.004) and displacement (p = 0.013) compared to alcoholics without malignant tumors who significantly more often used neurotic defense mechanisms - compensation (p = 0.005) and intellectualization (p < 0.001). the earliest emotional experiences and quality of family relations affect the development of defense mechanisms. These are the psychological factors in the development of oropharyngeal cancer in alcohol addicts.