The objective of this study was to explore societal awareness of stigma and discrimination against persons living with Human Immunodeficiency Virus (HIV) (PLHIV) through the experience of clinicians, PLHIV, the general population and persons who are vulnerable to HIV. This was a cross-sectional survey which used questionnaires to collect data during May to July, 2013. The sampling unit was eight target provinces of the National AIDS Program Plan (NAP) for 2012 to 16. The sample respondents include 300 persons in Internet on-line groups, 1,937 factory workers, 334 female sex workers (FSW), 317 men who have sex with men (MSM), 101 persons who inject drugs (PWID), 352 HIV clinicians and counselors, and 1,880 PLHIV. The sampling methods used a combination of time-location sampling and quota sampling. The factory workers were sampled with probability proportional to size and quota sampling. PLHIV were purposively selected at anti-retroviral therapy (ART) clinics. This study found that the respondents felt that Thai society still views PLHIV in a negative light and fear the consequences for themselves and their family if others knew they were HIV+. Self-stigma among vulnerable populations is still quite prevalent. MSM have less self-stigma than FSW, PLHIV and PWID. All of the vulnerable groups reported being treated differently (in a negative way) from the mainstream population, though this discrimination was not severe. Clinicians reported a slight amount of discrimination against the vulnerable populations but, generally, the goal was to treat all clients equally, without prejudice or stigma and discrimination, based on principles of human rights, regardless of gender or sexuality. Nevertheless, Thailand needs to continue to improve awareness and provide training in human rights, fundamental sex rights, and gender equity for health providers and other relevant individuals. There is a need for monitoring stigma and discrimination, and elimination of violence due to sexual diversity, both at the national and sub-national levels. Mass media is a crucial channel for improving attitudes, beliefs, knowledge and understanding in the area of human rights and respect for others rights, including empowering those impacted by stigma and discrimination, so that they know how to identify rights violations, seek protections from violations and redressing violations.