Rostislaw Kaischew (Bulgarian: Ростислав Атанасов Каишев; February 16, 1908 O.S.

)), Saint Petersburg, Russian Empire – November 19, 2002, Sofia, Republic of Bulgaria) was a Bulgarian physicochemist and a member of the Bulgarian Academy of Sciences.

His most significant contributions to science were within studies of crystal growth and nucleation.

[1][2] Kaischew graduated from Sofia University in 1930 and earned his doctorate at Technische Hochschule of Breslau, Germany in 1932.

At the Bulgarian Academy of Sciences, Kaischew founded the Institute for Physical Chemistry, and held the position of director there from its creation in 1958 until his retirement in 1989.