  We report preliminary results of a Dalitz plot analysis of three-body
charmless B0=>Kspi+pi- decays. The analysis is performed with a data sample
that contains 386 million $B\bar{B}$ pairs collected near the Y(4S) resonance
with the Belle detector at the KEKB asymmetric energy e+e- collider.
Measurements of branching fractions for quasi-two-body decays B0=>rho(770)0K0,
B0=>f0(980)K0, B0=>K*(892)+pi-, B0=>K*(1430)+pi-, and upper limits on several
other quasi-two-body decay modes are reported.
