Hypertension is one type of worldwide chronical desease that may cause complication with other perilous diseases. Preventive efforts are necessary to reduce hypertension rate, one of which is by pharmacotherapy. Control over medicine taking should be conducted at consistent and regular basis. This study is therefore aimed at identifying the behavior factor affecting patients' adherence to antihypertensive medicine taking. This study is descriptive qualitative analysis conducted at Pucang Sewu Local Government Clinic, Surabaya. Data collection was conducted with questionnaire and medicine prescription check. The data was analysed with Spearman correlation test to examine the efects of behavior factor upon patient's adherence to antihypertensive medicine taking. The result of the study shows that patients' adherence to hypertensive medicine taking at the Pucang Sewu Clinic was high, that of 72 samples, 51 respondents showed high adherence to antihypertensive medicine taking. The Spearman correlation test shows that patients's attitude significantly affect their adherence to antihypertensive medicine taking, with correlation coefficient 0.701 (significance < 0.0005), which is of the highest influence compared to other factors. Besides the patients' attitude, health facility and means have also affected significantly, while such factors as knowledge and pharmacist's behavior have insignificantly affected adherence to antihypertensive medicine taking in Pucang Sewu Clinic, Surabaya. Information on the influence of behavior towards adherence to antihypertensive medicine taking may help medical and pharmacy staff to decide medical steps for hypertension patients to reduce hypertension rate in Pucang Sewu Clinic, Surabaya.