Adrian Georg Iselin (January 17, 1818 – March 28, 1905) was a New York financier who invested in and developed real estate, railroads, and mining operations. For many years during his early business career he was engaged in importing with his brother, William Iselin, being one of the most successful merchants of New York in the middle of the century. After retiring from the importing trade, he established the banking house of Adrian Iselin & Co. He is considered the founder of the Iselin family in the United States.