This paper uses ARM7 processor LPC2290, embedded data acquisition chip AD7715 and real-time operating system μC/OS-II as a basis to design an ARM-based embedded data acquisition system. This system achieves RS-232/RS-485 communication, Ethernet communication, keyboard and LCD display embedded control applications. It has a small size hardware, low power consumption, plenty functions and highly extended features. The reliability of embedded real-time operating system μC/OS-II has been certified. It makes the system more stable, and makes maintenance and upgrade program more convenient.