  Latest general relativistic simulations for merger of binary neutron stars
with realistic equations of state (EOSs) show that a hypermassive neutron star
of an ellipsoidal figure is formed after the merger if the total mass is
smaller than a threshold value which depends on the EOSs. The effective
amplitude of quasiperiodic gravitational waves from such hypermassive neutron
stars is $\sim 6$--$7 \times 10^{-21}$ at a distance of 50 Mpc, which may be
large enough for detection by advanced laser interferometric gravitational wave
detectors although the frequency is high $\sim 3$ kHz. We point out that the
detection of such signal may lead to constraining the EOSs for neutron stars.
