The most difficult step in the morphological study of the internal organ-surface primo-vessel (Bong-Han duct) system is the correct identification of samples, due to similarities between torn mesentery and primo-vessel tissue. Without proper sample discernment, the subsequent parts of morphological studies cannot be trusted. Here, we present differences between torn mesentery and primo-vessel tissues as determined by minimal operation, using stereoscopic and microscopic observation. Stereoscopic observation revealed that torn mesentery is tightly connected to the organ surface and does not branch; the detached margin has a fan-shaped membrane without any swollen portions. Primo-vessels are slightly connected to the organ surface and branched, while detached margins lack a membrane and possess a swelling termed the primo-node (Bong-Han corpuscle). Microscopic observation shows bundle patterns in primo-vessel tissue, but irregular arrangement in torn mesentery tissue. These characteristics can be used to distinguish torn mesentery from primo-vessels.