Time-integrated spectra of second harmonic (2ω) light emission from plasmas produced with 1.053μm laser are simultaneously measured at several scattering-angles.By analyzing the relationship between scattering energy and scattering angle,also by analyzing the total 2ω light intensity as a function of incident beam intensity,we found that the Langmuir turbulence,which is produced by cascade of parametric decay instability,plays an important role in the laser-plasma interaction.