Abstract: Abstract: The radioative reagent diluting and dividing system exchanges information with human by using LCD screen and keyboard. Five high precision step-motors are used to make the mechanical arm with two injectors moving to three-dimentional location, and control the inhaleation volume of the two injectors. There are six singlechip in this system. All those singlechips are united to a cooperative system by serial-bus.This system can divide and dilute the radiotive reagent with high precision and no pollution