Ivan Nikolov Stranski (Bulgarian: ???? ??????? ????????; German: Iwan Nicolá Stranski; 2 January 1897 – 19 June 1979) was a Bulgarian physical chemist.The founder of the Bulgarian school of physical chemistry, Stranski is considered the father of crystal growth research.
Stranski headed the departments of physical chemistry at Sofia University and the Technical University of Berlin, of which he was also rector.
The Stranski-Krastanov growth and the Kossel-Stranski model have been named after Ivan Stranski.