For the purpose of meeting the rapid development of blood purification in China, improve the level of blood purification treatment, and get rid of the plight of the foreign technology monopolization to promise patients’ medical safety, a parameter-calibrator for the hemodialysis unit, which can detect simultaneously multi-parameter, is designed. The instrument includes a loop, which connects to the hemodialysis unit. Sensors are in the loop in series, so that the dialysis can flow through this loop and the sensors can acquisitive data of various parameters. In order to facilitate detection and carrying, the integrated circuit part modularly based on the ultralow-power microcontrollers,TI MSP430 is designed. High-performance and small-packaged components are used to establish a modular, high-precision, multi-functional, portable system. The functions and the key technical indexes of the instrument have reached the level of products abroad.