Abstract: Traditional health care equipments are unsuitable for mobile applications due to their large volume and high power consumption. In this paper, a wearable mobile device was designed for ECG, BP and SpO2 monitoring, which was mainly composed of the signal acquisition-processing board and then smart mobile phone. The mainboard which consists of a MCU and three kinds of signal acquisition front-end, was mainly used to acquire and process the physiological signals. Then the processed signals were transferred to a smart phone, which is utilized for display, storage and terminal control. In additional, the data charged by the phone can also be uploaded to a server through WIFI. The experiment results indicate that the device can meet the requirements of mobile health care, which is only 6 cm×9 cm×1 cm in size and the battery life is beyond 24 hours for the case of continuous work.