The upgraded low-level RF system of the PLS storage ring was installed in January 2002. The new system employs dual (inner and outer) amplitude and phase control loops. The inner loop operates mainly for compensation of RF signal phase and amplitude variations of klystron amplifier, and suppression of 60Hz harmonic noise from the amplifier. The inner loop has about 1 kHz bandwidth. The outer loop is active for controlling gap voltage and phase variation of the RF cavity. Bandwidth of the outer loop is about 100 Hz. The new system is consists of many modules that enable us easy maintenance. The new system has many monitoring points of RF and control signals for easy diagnosis. Design concepts and performance of the upgraded lowlevel RF system will be presented and discussed.