When constructing 3D printed concrete, it is important to set the appropriate fabrication conditions and printing parameters, such as printing material extrusion rate, printing path Pattern, printing time, printing speed and diameter of nozzle, in addition to selecting material and designing mix proportion. In the case of conventionally casted concrete member, a similar material property and structural performance can be basically achieved when using the same material and mix proportion under the equivalent environmental condition. In contrast, 3D printed concrete displays different material segregation, mechanical property, and fracture behavior with changing the printing parameters for building an object, even when using the same materials and mix proportions. This study aims to control and evaluate the material property and structural capacity alteration of 3D printed concrete based on the printing parameters. Especially, the material setting in printing procedure and the fracture mechanism are discussed by means of several non-destructive testing (NDT), e.g. X-ray CT and Acoustic Emission.