We have developed a low-power wide-dynamicrange readout system for a 64-channel multi-anode photomultiplier (PMT) of a scintillation gamma camera. Each anode is individually read with the system that contains discrete devices of amplifiers, comparators, sample-hold ADCs, and FPGAs. The size of the system which is designed for a twodimensional array of Hamamatsu flat panel PMT 88500 is 5×5×14 cm3. The input dynamic range is variable by replacing the feedback capacitor of the preamplifier (e.g., 700 pC and 4000 pC for GSO(Ce) and LaBr3(Ce) crystals, respectively). The serialized ADC data are sent to a VME sequence module. The total power consumption is 1.6 W per 64 channels. With this system we have developed a gamma camera using an 8×8 array of GSO(Ce) pixels with a pixel size of 6×6×13 mm3 coupled to an H8500, and btained flood-field irradiation images at energies from 30 keV to 1.3 MeV. The energy resolution was 10.8±0.4% (FWHM) at 662 keV. In addition, we used the readout system for an 8×8 array of LaBr 3(Ce) pixels with a pixel size of 6×6×15 mm3 and obtained a flood-field irradiation image at 662 keV.