This paper presents an efficient manual control parameter tuning for positioning controllers in high-performance industrial mechatronic systems. Owing to the complexity of control theory, manual parameter tuning is generally performed by engineers who are unfamiliar with the theory. For instance, the control stability (i.e., gain margin and phase margin) in a feedback (FB) control system often deteriorates the tuning efficiency (time for tuning) due to the trade-off between stability and control bandwidth. Therefore, it takes a long time to acquire expert tuning skills by the trial and error method, which is based on human intelligence. In this study, we propose an optimization problem-based technique for the calculation of a stable FB control parameter area to give unskilled adjusters a visual area of stable parameters, in order to improve the tuning efficiency. The effectiveness of the proposed approach is verified by conducting experiments with a FB controller for the fast and precise positioning control of a galvano scanner.