The study was to determine the effect of local anesthetics phonophoretic. Emla 5%(lidocaine+prilocaine) cream make use of medicines. Phonophoretic the application of a ultra sound(I group), application an ointment(II group). Forty college student between the age of man $22.85{pm}3.31$ woman $21.05{pm}2.12$, weight of man $70.70{pm}9.43;kg$ woman $50.65{pm}5.13;kg$, height of man $17.6{pm}5.43;cm$ woman $161.20{pm}4.34;cm$ were in this study. The results was as follows. There was statistical difference between I group($49.25{pm}10.83$) and II group($58.90{pm}10.83$) for the timing of local anesthetics(p<.05).