Aiming at solving the problem of inaccurate control and multivariable coupling in aquiculture process, a monitoring and feed forward decoupling for multivariable fuzzy decoupling control system based on PROFIBUS for aquiculture was presented. The control system combined the PROFIBUS and intranet was built, the intelligent control and share of its information in aquiculture process were realized with this system. Fuzzy controllers and decoupling units were designed dependently, where the neural network with a single hidden layer was employed for decoupling. The simplified training algorithm based on the system output error was used for online adjustment of the network weights and realizing dynamic decoupling, the test results have shown that the method is effective.