Abstract: This paper concerns one dimensional (1D) nonlinear wave equations. We can prove the existence of a Whitney smooth of smallamplitude quasiperiodic solution under the antiperiodic boundary conditions. The proof is based on an infinitedimensional KAM (KolomogorovArnoldMoser) theorem.

Key words: wave equation, antiperiodic boundary, infinite KAM theorem, quasiperiodic solutions