Magnesium nitrate is a hygroscopic inorganic compound with the chemical formula Mg (NO3)2. Magnesium nitrate can be found in the earth’s crust, as its hexa-hydrate form, like nitro magnesite salt; that is a rare mineral form of magnesium nitrate. It is a highly water-soluble compound.

By heating, another hexa-hydrate salt does not give anhydrous magnesium nitrate, and it needs to manufacture in the laboratory.