H∞ norm is widely adopted in control system design and its model-based computation is well-established. In these applications, the optimization of the H∞ norm follows an offline manner. However, the real-time optimization of the H∞ norm of a (stable) linear time-invariant system remains open, which is of considerable interest in the domains of performance optimization, fault-tolerant control, etc. Driven by this desire, as an alternative to the model-based offline solution of the H∞ control/optimization problem, this paper proposes a real-time H∞ norm optimization approach. It would be beneficial to the real-time reconfiguration of the controller/observer under the H∞ optimization framework.