An experimental investigation has been made with the objective of studying the mixing mechanism near the nozzle exit in a tone excited non-premixed jet flame. The fuel jet was pulsed by means of a loudspeaker-driven cavity. The excitation frequencies were chosen for the two cases of the non-resonant and resonant frequency identified as a pipe resonance due to acoustic excitation. The effect of different sinusoidal excitation conditions on mixing pattern near the nozzle exit and flame was visualized using various techniques, including schlieren photograph and laser light scattering photograph from TiO2seed particles.