Diesel sprays impinged on a flat wall and an extruded column surface were investigated experimentally. The purpose of this study is to clarify the effect of diameter of extruded wall on spray growth behavior after impingement. High-pressure injection system was used for the spray formation. The sequential photographs of spray growth were taken by a high-speed drum camera. Spray volume after wall impingement was derived from the photographs. The result showed that the spray shape after the impingement was remarkably changed by the effect of extruded column. Also, it was found that there was the optimum diameter of the extruded column for increasing of spray volume.