A systematic design procedures of dynamic positioning system are proposed in view of practical design work for higher efficiency and reliability. In order to make an approach to better dynamic positioning control for given environmental conditions, detailed investigations were carried out on the filtering technique for positional signals. Evaluation of the technique was made on the basis of computer simulations by use of ship motion theory and model test results. It is clarified that the technique will substantially provide an efficient way to the better control performance of dynamic positioning systems.