  We have measured the cross section for pi^0 pi^0 production in two-photon
collisions using a data sample with an ntegrated luminosity of 95 fb^-1
collected with the Belle detector. We find at least four resonant structures
including a peak from f_0(980), and a fitting of the result to partial-wave
amplitudes assuming some resonances are applied. We also make a discussion on
the higher-energy region data based on the preliminary results from an
increased sample corresponding to the integrated luminosity of 223 fb^-1.
