Blanca de Castejón Otero (Comerío, Puerto Rico, 13 de maig de 1906 - Mèxic DF, Mèxic, 26 de desembre de 1969) va ser una actriu porto-riquenya que es recorda sobretot pel seu treball a l'Edat d'Or del cinema mexicà.

María Blanca Josefina Regalado Castejón y Otero (May 13, 1906 – December 26, 1969), better known as Blanca de Castejón, was a Puerto Rican actress who is best remembered for her work in the Golden Age of Mexican cinema, especially her award-winning supporting role in Escuela de vagabundos (School for tramps, 1953).