Abstract: This study used a smartphone eye-tracking approach to examine understudied areas in health communication – hope in fear appeal – when people are exposed to differential emotional shifts with fear and hope on social media. In an image presentation with 4 (fear only vs. fear-then-hope vs. fear and hope vs. hope-then-fear) between-subjects eye-tracking experiment, participants viewed Instagram posts with variation of emotional shifts, then answered a questionnaire containing measures including perceived self-efficacy and intent to engagement of diabetes preventive behavior. Results indicated that emotional shift from fear to hope influences message processing through raising participants’ perceptions of self-efficacy compared to fear-only image social media content. The research also showed that fear-based images increased people’s attention to efficacy information followed by fear and hope, fear-then-hope, and hope-then-fear condition. Implications for health communication theory and practice are further discussed.