Where is professor snapes office in harry potter 5-7?

In "Harry Potter and the Order of the Phoenix," Professor Snape's office is located in the dungeons of Hogwarts School of Witchcraft and Wizardry. It is described as a dark, cold space filled with various potion ingredients and has a distinctive, musty smell. The office is accessed through a stone door at the end of a long, dimly lit corridor that leads down from the castle. This setting reflects Snape's personality and his role as the Potions Master at the school.