Background: The use of digital health technology in diabetes self-care is increasing, making eHealth literacy an importantfactor to consider among people with type 1 diabetes. There are very few studies investigating eHealth literacy among adultswith type 1 diabetes, highlighting the need to explore this area further.Objective: The aim of this study was to explore associations between eHealth literacy and demographic factors, disease-specific factors, and well-being among adults with type 1 diabetes.Methods: The study used data from a larger cross-sectional survey conducted among adults with type 1 diabetes in Sweden(N=301). Participants were recruited using a convenience sampling method primarily through advertisements on social media.Data were collected between September and November 2022 primarily through a web-based survey, although participantscould opt to answer a paper-based survey. Screening questions at the beginning of the survey determined eligibility toparticipate. In this study, eHealth literacy was assessed using the Swedish version of the eHealth Literacy Scale (Sw-eHEALS).The predictor variables, well-being was assessed using the World Health Organization-5 Well-Being Index and psychosocialself-efficacy using the Swedish version of the Diabetes Empowerment Scale. The survey also included research group–developed questions on demographic and disease-specific variables as well as digital health technology use. Data wereanalyzed using multiple linear regression presented as nested models. A sample size of 270 participants was required in orderto detect an association between the dependent and predictor variables using a regression model based on an F test. The finalsample size included in the nested regression model was 285.Results: The mean Sw-eHEALS score was 33.42 (SD 5.32; range 8‐40). The model involving both demographic anddisease-specific variables explained 31.5% of the total variation in eHealth literacy and was deemed the best-fitting model.Younger age (P=.01; B=–0.07, SE=0.03;95% CI –0.12 to –0.02), lower self-reported glycated hemoglobin levels (P=.04; B=–0.06, SE=0.03; 95% CI –0.12 to 0.00), and higher psychosocial self-efficacy (P<.001; B=3.72, SE=0.53; 95% CI 2.68-4.75)were found associated with higher Sw-eHEALS scores when adjusted for demographic and disease-specific variables in thismodel. Well-being was not associated with eHealth literacy in this study.Conclusions: The demographic and disease-specific factors explained the variation in eHealth literacy in this sample. Furtherstudies in this area using newer eHealth literacy tools are important to validate our findings. The study highlights theimportance of development and testing of interventions to improve eHealth literacy in this population for better glucosecontrol. These eHealth literacy interventions should be tailored to meet the needs of people in varying age groups and withdiffering levels of psychosocial self-efficacy.