As it is known, the anatomy of the vessels is examined by removing the cast of the vessels inside the organs. Generally, liquid material (polyester, takilon, etc.) is injected into the vessels with positive pressure to remove the cast from the vessels of the organs. We built a machine to remove the cast of the vessels inside the organ. We named it corrosion machine.Sheep kidneys were used in our experiment. After the kidneys were cannulated, they were placed in the vacuum chamber. With the operation of the vacuum pump, negative pressure was created in the vacuum chamber. With negative pressure, kidneys and its vessels expanded. Takilon or polyester easily entered the vessels of the kidney. The cast of the vessels of the kidney was removed. With this newly developed technique, the anatomy of the vessels whose casts were removed was examined with the naked eye, stereomicroscope or SEM.The corrosion machine we built can cast the vessels of the organs very well. Takilon or polyester (which we used in our experiment) easily entered the capillaries under the effect of negative pressure.We think that this method can also be applied to other organs and used in vascular research.