Endoscopic rhinosurgery of paranasal sinuses and the anterior base of the skull has been extensively developed during the past decades. The practical application of the endoscopic surgical techniques requires excellent knowledge of ethmoidal bone embryogenesis and anatomy based on the in-depth investigations into the autopsy materials that provides a solid basis for the successful surgical treatment of the pathological changes in this region. There are neither Russian-language atlases nor guidelines considering ethmoid anatomy in terms of endoscopic rhinosurgery. At the same time, the understanding of the formation of the main anatomical landmarks of the ethmoidal bone in the course of embryogenesis as well as their visual observation and three-dimensional imaging is indispensable for the adequate operations on the ethmoidal labyrinth even in the case of disturbances in the normal ethmoid anatomy associated with the pathological processes. The objective of the present work was to create the guidelines for the endoscopic dissection of the ethmoidal bone in order to facilitate orientation in this anatomical region for the rhinosurgeons. For this purpose, we provide the large number of endophotographs together with certain subtle details of importance for the practicing rhinologists.