This paper presents the study of acoustic wave propagations in two dimensional domains with unstructured nodal high-order Discontinuous Galerkin (DG) nethod. The DG method employs triangular elements and uses piecewis high-order Koornwinder Dubiner polynomials for spatial discretization and low storage fourth order Runge Kutta for time integrations. Fluxes are calculated by using upwind fluxes. After demonstrating the exponential convergence of the DG method, the acoustic wave propagatens in complex domains are studied.