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The characteristics of diesel spray under the condition of super high injection pressure and the coupling effects between the spray and induced shock waves have been widely concerned. In this study, under the injection pressure up to 300 MPa, the spray penetration and spray angle were measured via high speed camera and the progressing process was compared with the existing spray empirical formula. The induced shock wave was captured using the Schlieren system when the spray tip velocity is greater than the ambient sonic speed (340m/s at room temperature). The second shock wave appeared behind the leading shock wave when the injection pressure up to a certain value while the distance between the leading and second shock wave was closely related to the injection pressure. Owing to the existence of shock waves, the spray morphology (spray front angle) had been greatly affected and conversely the wave morphology (circular arc or circular cone, leading shock wave angle) changed with the increasing injection pressure. The results in this paper show that the spray characteristics under super high pressure were quite different to those of conventional spray, and the variation of droplet diameters is increased and then remained stable with increasing injection pressure.