This study presents an advanced current control of permanent magnet synchronous motor (PMSM) aiming for improved transient performance over a wide speed range. While the conventional current control scheme based on proportional-integral controllers often shows a degraded transient performance in high-speed operation where the control inputs are almost saturated, the proposed scheme uses a proportional current controller in combination with a disturbance observer, by which the current error converges to zero in an exponential way. This desirable property preserves the transient performance even under the input constraint. A systematic way to determine the optimal control gain considering parameter uncertainties is also provided. A simulation study verifies the efficacy of the proposed scheme using a 20 kW PMSM model in comparison with the conventional current control scheme.