Background: Adherence to antihypertensive medication is key component for the hypertension. Nonadherence to these medications will results in the complications of hypertension like stroke. The adherence level and associated factors to antihypertensive drug in the study area identified. Objectives: To assess adherence and associated factors of antihypertensive drug among adult hypertensive patients at chronic follow up clinics of West Gojjam. Methods and materials: Institutional based cross-sectional study was conducted in chronic follow up clinics randomly selected hospitals from Jun1/2020-Jun15/2020. Multi stage sampling technique was used and pretested structured questionnaire with review of medical charts, and the MMAS-8 tool used to assess the adherence status. Data entered to Epi-Info version-7.3 and analyzed by SPSS version-25. Variables with P-value < 0.25 in bivariate logistic regression analysis entered in to the multivariable logistic regression. P-value < 0.05 used to determine the presence of statistical association with fitted model. Result: five hundred forty one hypertensive patients were participated with a response rate of 96.9%. The mean age of the participants was 54.39 and SD of ±11.4, and 60.6% participants were male. The adherence level of the participants was 61.4% (95%CI=0.573-0.655). Factors like, abused by alcohol (AOR=0.213,95%CI=0.072-0.632), rural residency (AOR=0.423, 95% CI=(0.224-0.798), forgetful of taking the medication(AOR=0.116-95%CI=0.063-0.213), poor knowledge (AOR=0.191, 95%CI=0.085-0.43), and thinking antihypertensive drug as non-useful (AOR=0.537, 95%CI=0.309-0.936) were negatively associated with adherence. Conclusion: The adherence level of the participants found below the WHO standards. Adherence to antihypertensive drug affected by the residency, knowledge status, forgetfulness, attitude towards the medications, and alcohol abuse. The attitude of hypertensive patients about the usefulness of the antihypertensive medications should improve. Key words: Adherence, Hypertension, antihypertensive drugs