The invention is directed to novel heteroaryl peptidomimetic compounds which are useful as thrombin receptor antagonists for the treatment of diseases associated with thrombosis, restenosis, hypertension, heart failure, arrhythmia, inflammation, angina, stroke, atherosclerosis, ischemic conditions, angiogenesis and related disorders, cancer, and neurodegenerative disorders. Pharmaceutical compositions comprising the substituted heteroaryl peptidomimetics of the present invention and methods of treating conditions mediated by the thrombin receptor are also disclosed.