A two dimensional CsI(Na) scintillation plate with high spatial resolution has been developed by growing CsI(Na) crystal on a special fiber plate with fiber size of 20 μm. The number of photons at the output were 34 photons for 55Fe and 260 photons for 129I respectively. The spatial resolution measured by electron beam excitation showed approximately 30 μm of FWHM. Detection efficiency of the plate with 120 μm crystal thickness was measured to be about 23 % for 129I referring to a standard NaI(Tl) scintillator.