Background: Oral Anti-coagulant is widely used for the prevention and treatment of cardiac and thromboembolic diseases. As oral anticoagulant is a narrow therapeutic index medicine, it requires close monitoring to achieve effectiveness of anticoagulants therapy. Therefore, this study was conducted to assess adherence to anticoagulant therapy and its awareness among cardiac patients attending cardiac OPD of Chitwan Medical College Teaching Hospital, Chitwan. Methods: A descriptive cross-sectional study design was carried out among 91 cardiac patients attending cardiac OPD of Chitwan Medical College Teaching Hospital sample was selected by using Consecutive sampling technique. Data was collected using structured interview schedule. General medication adherence scale and self-prepared structured questionnaire of awareness of anticoagulant therapy was used.  Data was analyzed in SPSS version 20 by using descriptive and inferential statistics. Results: Out of 91 respondents 42.9% of the respondents had partial adherence while 33.0% had good adherence. Only 6% of the respondents had high adherence, 7.7% and 9.9% of the respondents had poor and low respectively. Regarding awareness of anticoagulant therapy 63.7% of the respondents had inadequate level of awareness. There was statistically significant relationship between level of awareness with educational status (0.02), having insurance (0.05) and drug duration (0.05). Conclusions: Based on this finding respondent’s awareness was found to be low on the risk effects of alcohol intake, drugs and food interaction and self-limiting of injurious activities and most identified reason for non-adherence is discontinue due to feeling well, adverse effect and progression of disease. So, clinician and nurse should design an effective instructional program about anticoagulant therapy by highlighting those limited area thus to enhance adherence and prevent life threatening complications.