Abstract: Existential Anxiety is one of definitions of anxiety ontology, and is one of the important concepts in philosophy, literature and psychology. The theory mainly includes anxiety ontology put forward by Rollo May, existential anxiety by James F. T. Bugental and the interaction between existential anxiety and mental health. However, the present method of study -- scale measurement, is still immature. There is not much empirical research which focuses on the relation between existential anxiety and mental health, existential anxiety and self-identity, existential anxiety and anxiety and depression, and so on . Enrichment of the study of conception, broadening of objects of study, improvement of approaches of research are the trends of research in this field

Key words: existential anxiety, anxiety ontology, mental health