This control system (100) for at least one Jacquard mechanism (4) for forming shed comprises electromechanical selection devices (20) including magnets, a primary controller (70) intended to communicate with a weaving machine (2) and including at least one memory (76) to store weave pattern data and at least one computer (74). This system also comprises at least two secondary controllers (40A, 40B), each electrically connected to the primary controller (70) and each able to control a group of electromechanical selection devices (20), each secondary controller comprising at least one memory (46A, 46B) for storing weave pattern data and at least one computer (44A, 44B), as well as control units (30) for the electromagnets belonging to the electromechanical selection devices (20). This system further comprises at least one intermediate controller (50) in direct electrical connection, on the one hand, with one of the secondary controllers (40A, 40B) and, on the other hand, with at least two electromagnet control units (30).