We investigated self-esteem, personality type and gender as factors in self-disclosure among adolescent social network users. Participants were drawn from St Catharine’s School and Anglican Grammar School. A total of three hundred and fifty (350) students (comprising SS1 and SS2)- 190(54.3%) females and 160 (45.7%) males participated in the study. Their ages ranged from 12-23 with a mean age of 17.5 years. The participants were selected using random sampling method. Three instruments were used for data collection: Index of self-esteem (ISE), Big Five Factors (dimensions) of Personality (BFI) and Self-Disclosure Index (SDI). The objectives of the study were to ascertain whether:1) self-esteem would significantly predict self-disclosure among adolescent social network users. 2) Personality type would significantly predict self-disclosure among adolescent social network users. 3) Gender would significantly predict self-disclosure among adolescent social network users. Linear regression statistics was used to test the hypotheses and the results showed that self-esteem did not significantly predict self-disclosure among adolescent social network users. Agreeableness (β = -.45, p < 0.01) and conscientiousness (β = .32, p < 0.05) significantly predicted self-disclosure among adolescent social network users. Self-disclosure among adolescent social network users was not predicted by gender. Implications and limitations of the study were discussed and suggestions for further studies offered.