Objective: The objectives of this study are to evaluate the relation between internalized homophobia and suicidal ideation in young lesbians, gays, bisexuals and heterosexuals; and also assess the influence of gender, discrimination experiences and disclosure of sexual orientation on suicidal ideation. Method: Participants- the sample consists of 389 participants, with a mean age of 19 years old. 51.9% were men and 48.1% were women. Regarding sexual orientation 36.0% were gay, 25.2% bisexual, 21.9% lesbian and17.0% heterosexual. The majority assume having already come out (61.4%). Most of the participants were in high school (51.4%).Instruments-we used a Demographic Questionnaire, the Suicide Ideation Questionnaire (SIQ) (Cronbach’s alpha=0,975), and the Internalized Homophobia Questionnaire (Cronbach’s alpha=0.81).Procedure – the data collection was done using the Internet. The questionnaires were available on a website built solely for this study. Publicity to this website was done through virtual communities, e-mail and several youth forums. Results: The results support the idea that there is a positive and statistically significant correlation between internalized homophobia and suicidal ideation. In addition, it was found that gay youngsters are the ones who have a stronger internalized homophobia, while young bisexuals are the ones who have higher levels of suicidal ideation. The teenagers who have not, yet, made their disclosure of sexual orientation and those who experienced discrimination, due to their sexual orientation, are those who had higher levels of suicidal ideation. Conclusion: More emphasis should be placed on suicide prevention for younger LGB individuals, in addition to the current emphasis on suicide prevention for adults. Future research should continue to examine unique, understudied LGB communities.