Abstract: In this paper it is demonstrated that the south-pointing-chariot invented about twothousand years ago is an open-loop regulating system based on the disturbance compensa-tion principle. And about nine hundred years ago in North-Song Dynasty, Su Sung andHan Kung-lien built a water-powered astronomical apparatus, in which a balancing de-vice, an automatic controller activated by the error of the regulated variables, was used.The block diagrams and transfer functions of these two systems are given in this paper. Two parameter stabilizing systems, namely, the water clock and the constant speeddriving system in the water-powered astronomical apparatus are also introduced. Inboth cases, the influence of the external disturbances upon the stabilized variables areautomatically compensated. The author analysed the various automatic equipments in Ancient China andgrouped them into six classes: automatic transducing and signalling system, open-loopcontrol system, open and closed-loop regulating system, open-loop programming system,parameter stabilizing system and simulation of the systems. It is concluded that achieve-ments in automatics in Ancient China was quite significant compared with the situationthen existing in other countries.