Purpose– This paper examined the sexual orientation disclosure of LGB (lesbian, gay , bisexual) staffs in the Vietnamese working environment along with its antecedents and consequences. Design/methodology/approach– The method was mainly quantitative but qualitative method was also used to modify the scales. 20 LGB staffs were interviewed and 320 people in this community validly returned the questionnaire. Findings– The results showed that sexual orientation disclosure had a certain impact on LGB staffs’ work attitudes, but the higher effect belonged to company support. Reaction of coworker also had a small influence to the attitudes. In terms of antecedents of disclosure, personal characteristic played the biggest role, followed by company support and perceived social support. One more useful information was that LGB employees manifested their sexual orientation at different levels in diverse types of company in Vietnam. Research limitations/implications– Some other valuable dependent variables have not been considered in this study, such as LGB worker''s job anxiety, mental health. The "policy" factor is only mentioned in a very general way. Further studies in Vietnam may consider these factors more carefully. Practical implications– Solutions for LGB employees, coworkers, managers and the whole society are addressed to improve the working environment for LGB workers in Vietnam. Originality/value– This is the first academic research on sexual orientation disclosure at work in Vietnam, in which, perceived social support is a new element that we introduce into the context of Vietnam. This provides the first comparison of disclosure between types of enterprises.