High blood pressure is one of the main reason which causes stroke and cardiovascular disease, and the measurement of blood pressure is very important for the management of hypertension. There are various automatic blood pressure measurement devices developed which could easily measure blood pressure at home and daily life. However, the problem exists among different types of automatic blood pressure devices because of no standard algorithm for estimating accurate blood pressure values. Standard method for indirect measurement of blood pressure is based on Korotkoff sound to determine systolic and diastolic blood pressure. However, there are no automatic devices exist which measures blood pressure based on the detection of korotkoff sound because of manufacturing cost and difficulties of detecting sounds. In this study, PVDF film was used to as a vibration sensor detect Korotkoff sound on the brachial artery. To remove unwanted pulse signal, 4th order 35Hz highpass filter and amplifiers were designed in house. For data acquisition, ten subjects were participated for the study and the procedure was set based on international protocol for the validation of blood pressure measuring devices. The results showed that the blood pressure values obtained from newly developed device has high correlation with those from auscultatory method. Correlation coefficients between auscultatory method and developed method were 0.977 and 0.968 for systolic and diastolic, respectively. Standard deviations of auscultatory method were 1.66-4.71mmHg and 1.77-4.78mmHg for systolic and diastolic, respectively. Standard deviations of developed divice were 3.03-5.94mmHg and 2.00-5.68mmHg for systolic and diastolic, respectively. Validation results based on the international protocol shows 95% and 91.6% belong to group A for systolic and diastolic, respectively. Future study will be performed to improve algorithm and to validate developed device under the international standard. Once the device is customized, it would help patient to measure accurate blood pressure in daily life easily and to help effective management of hypertension.