An electrocardiogram (ECG) is an essential way for diagnosing the heart disease, and the test theories and systems work well with the practice application, whereas, as new technologies and devices come forth one after another, it allow us to acquire the ECG data more conveniently, more accurately, more comprehensively. The authors discuss the design of ECG data acquisition system based on the USB 2.0 protocol, and expatiates the system principle in detail. The system employs two AD73360 to sample the standard 12-lead signal simultaneously, which has a resolution of 16-bit. They utilize EZ-USB FX-2 as the USB interface device, which can transfer the data conveniently and quickly, and also permit the configuration of multi-system controlled by just one host. Considering the DSP as a powerful tool in the field of digital signal processing, ADSP-2181 has been chosen.