An industrial control network with high accuracy should be established for measurement and setting out of batches of industrial components. The operational mode with on-line stations on observation pillars have the advantages on tripods in velocity, accuracy and reliablity. Building and actual accuracy (± 0.1mm) Of the industrial horizontal control network with 8 observation pillars have been introduced by Feng, et al (1999). A simple procedure for determining relative elevations of observation pillars is proposed for measuring the heighs of its all neighbor pillars on each station, with height gauge (0. 02mm of mimimal reading) and NA2 model pendulum level made by Leica company, Sweden. As a result, closing error for each circuit in the network is no more than 0.05mm. The key techniques are: ①horizontality of the upper surface of the observation pillar is made less than l'; ②The special marker on the upper surface of the pillar is used as a target which is used to transmit its height to the station; and ③The distance between neighbor pillars is no more than 9m.