This study examined the relation of self-esteem with sex and age for 660 Spanish students (400 secondary school students, 260 university students, age range 12 to 28 years), who responded to the Rosenberg Self-esteem scale. Analysis indicated no sex differences in general self-esteem, but there were differences with respect to age. Persons 12 to 16 years old had lower self-esteem than others between the ages of 17 and 28 years.