Self esteem is an important determinant of psychological well being that is particularly problematic during adolescent life stage. There is a correlation between low self esteem and other social problems among today’s adolescents. This study was conducted to determine the mean self esteem score and to determine the association between self esteem and age, sex, race, religion, number of siblings, ranking among siblings, family function, parental marital status and smoking among adolescents aged 12 to 20 years old. A cross sectional study design using random cluster sampling method was done. Four out of a total of 35 secondary schools in Klang District, Selangor were selected. Respondents consisted of individual students in selected classes from the four selected schools. Data was collected using a self administered, structured, pre tested questionnaire and was analyzed using the SPSS version 12.0. Out of 1,089 respondents, 793 completed the questionnaire (response rate 73.82%). The overall mean self esteem score was 27.65. The mean self esteem score for males (27.99) was slightly higher than females (27.31). The differences in the mean scores by race were statistically significant. There was a statistically relationship between mean self esteem scores and sex, age, race, religion, number of siblings, smoking and family function. There was no statistically significant difference between mean self esteem score with parental marital status and with ranking among siblings. The overall mean self esteem score was 27.65. Self esteem was associated with sex, age, race, religion, number of siblings, smoking and family function.