A consistent association has been observed between leukocyte telomere length (LTL) and atherosclerosis, but the mechanisms underlying these associations are still not well understood. Premature biology aging was evident in atherosclerotic plaques, characterized by reduced cell proliferation, irreversible growth arrest and apoptosis, and telomere attrition. As atherosclerosis is a state of chronic low-grade inflammation and increased oxidative stress, shortened LTL in patients with atherosclerosis might stem from the two sources, one is an accelerated rate in hematopoietic stem cells (HSCs) replication to replace leukocytes consumed in the inflammatory process, and another is the increase in the loss of telomere repeats per replication. Thus, diminished HSC reserves at birth and age-dependent telomere attrition afterward are mirrored in shortened LTL during the adulthood. In addition, the inter-individual variation of LTL in the general population can be partly explained by genetic factors regulating telomere maintenance and the rate of HSCs replication. Atherosclerosis is an aging-related disease, and practically all humans develop atherosclerosis if they live long enough. Here we overview the potential roles of LTL dynamics in the imbalance between injurious oxidative stress/inflammation and endothelial repair during the pathogenesis of age-related atherosclerosis, and discuss the possibility that preventing accelerated cellular senescence is a potential target in prevention of atherosclerosis.