A non-blinded parallel group randomized controlled trial is conducted. Adult male full-time employees of factories in Shenzhen who have access to smartphone and WeChat are recruited by staff of the Longhua Center for Disease Control and Prevention (CDC).

After completing an online baseline questionnaire, participants will be randomized evenly to either the intervention group or the control group. Participants in the control group will have access to a WeChat Mini Program providing HIV and sexually transmitted prevention information during the project period. In addition to those received by the control group, the Mini Program will proactively ask participants in the intervention group some simple questions to assess presence of sexual risk behaviors at Month 0 and Month 1, and invite them to watch online health promotion video(s) tailored to their current sexual risk behaviors.

All participants will complete two online follow-up surveys six and twelve months after completion of the interventions.

Inclusion Criteria:

• Male at birth
• Aged 18 years or above
• Full-time employee of a factory in Shenzhen
• Having a smartphone with internet access
• Having installed or willing to install WeChat on the smartphone
• Willing to complete follow-up surveys at Month 6 and 12

Exclusion Criteria:

• Oral or anal sex with a man
• Blindness ot deafness
• Not able to communicate effectively with project staff
• Self-reported as HIV positive

Male at birth

The data involve sensitive sexual behaviors of the participants