OBJECTIVE: The growing use of social networking services (SNSs) has impacted how patients with systemic lupus erythematosus (SLE) access health information, potentially influencing their interaction with healthcare providers. This study aimed to examine patients' preferences, actual use, and trust in various health information sources, along with the factors influencing the trust among patients with SLE. METHODS: A multicenter cross-sectional survey was conducted from June 2020 to August 2021, involving 510 Japanese adults with SLE. Participants reported their preferred and actual sources of health information, including SNSs, and their level of trust in these sources. Modified Poisson regression was used to analyze factors influencing trust, including internet usage and health literacy (HL) (functional, communicative, and critical). RESULTS: Most respondents (98.2%) expressed trust in doctors, while trust in websites/blogs (52.0%) and SNSs (26.8%) was lower. Despite this, the internet was the most frequent initial source of health information (45.3%), encompassing medical institution websites, patient blogs, X (formerly Twitter), and Instagram. Longer internet usage periods were associated with a greater trust in websites/blogs and SNSs. Higher functional HL was correlated with an increased trust in doctors but decreased trust in websites/blogs and SNSs. Higher communicative HL was linked to a greater trust in doctors, websites, and blogs. CONCLUSION: Although many patients with SLE initially seek health information online, they prefer consulting rheumatologists. Internet usage duration and multidimensional HL influence trust in online sources. Healthcare providers should consider these factors when disseminating health information and engaging with patients.