The complexity of geotechnical engineering and variability in construction circumstances of large extra caissons make the problem of maintaining appropriate sink attitude quite difficult, especially in keeping sink uniformity and achieving the expected final sink depth. A new construction control method is presented using (H∞) theory, considering uncertainties in the mechanics model and external noise in the construction site parameters. The design method of an (H∞) controller has consequently been obtained for large extra caissons. Control results using only constructor experiences are compared with simulation results using the (H∞) controller for a practical engineering situation, which indicates that the (H∞) controller is successful in maintaining sink uniformity, avoiding sink as well as in achieving the expected final sink depth.