Crash-test is the most basic and effective method of comprehensive evaluation on automobile security performance. Reference wall is one of the most important elements in the Deformation Measurement and Analysis System (DMAS), which is composed of more than 100,000 codes and targets, and provides standard value for the system to get automobile body deformation volume. A field calibration method for the reference wall of crash-test was presented in this paper, which improves the precision of calibration through proper redistribution by using photogrammetric system and scale bar, and the RMS is 0.05mm.