Objective  To conduct an empirical study on the situation and influencing factors of sexual activity with online partner seeking among rural elder unmarried men in China based on the theory of planned behavior.

  Methods  We conducted a computer assisted personal interview (CAPI) among 735 rural unmarried men aged 28 years and above recruited with cluster sampling and convenient sampling in 20 central and western provinces and three municipalities with large migrant population between January and September 2017.

  Results  For all the participants, the mean age was 33.4 ± 4.5 years and 118 (16.05%) reported ever having sex with online partners. The results of logistic regression analysis demonstrated that migration activity (odds ratio OR = 2.044), age (OR = 0.914), being drunk frequently (OR = 3.560), acceptance with online partners (OR = 2.252), and perceived friends′ norms (OR = 0.390) were significantly associated with having sex with online partner among the participants and the influencing factors differed between the left-behind participants and those being on migration. The perceived friends′ norm significantly affected sexual activity with online partner seeking only among the participants being on migration (P < 0.001); while, trust in online partner and monthly income affected sexual activity with online partner seeking significantly only in the left-behind participants (both P < 0.1).

  Conclusion  The prevalence of sexual activity with online partner seeking is relatively high among rural elder unmarried men with migration experience. The theory of planned behavior could well explain and predict the occurrence of sexual activity with online partner seeking.