Experimental results for the buckling process of cylindrical shells fully filled with water under axial impact are reported. Low velocity and large mass impact tests are carried out by means of a dropping hammer device. The experiment indicates that the buckling of shells takes place in an axisymmetric mode, and the whole impact process can be divided into three stages, i.e. dynamic loading, dynamic post-buckling and elastic unloading. The effect of the height and thickness of the cylindrical shells on the phenomena is discussed.