Traumatic stress can alter allostatis and therefore mediate the development of psychological disorders. Recent evidence from molecular studies has shown that telomere length - a measure of cellular aging - is strongly influenced by a broad spectrum of stress. Telomere erosion might be accelerated by traumatic stress, and traumatic stress has shown to be associated with the risk of developing chronic diseases like cancer, cardiovascular diseases and immunologic conditions. Aim: The biological pathways between psychological stress and psychological disorders or physiological diseases are widely unknown. Some experimental studies in animal models and longitudinal studies in humans have investigated the transgenerational consequences of psychological stress on telomere length biology. Telomere length inheritance might provide an additional molecular mechanism for the germ line transmission of environmentally induced phenotypic change and might offer a new biological framework for the multifactorial path etiology underlying stress-related disorders. Procedure: Starting from the well-established allostatic load model, this article reviews theoretical and empirical work from animal models and humans in the field of telomere biology in association with traumatic stress, childhood trauma and post-traumatic stress disorders. Further it reviews recent approaches on telomere length inheritance, and combines these findings with transgenerational research of post-traumatic stress disorder biology. Conclusion: A better understanding of the transgenerational mechanisms underlying common diseases might ultimately help disease prevention of stress related disorders in subsequent generations.