This study surveyed 96 high school students via questionnaires, adopting descriptive statistics, correlation analysis, and theoretical frameworks (Uses and Gratifications, Theory of Planned Behavior) to explore social media’s influence on their consumption preferences and financial traits. Data was analyzed using MATLAB R2023b. Key findings: 42.7% use social media 1–3 hours daily, with short-video platforms dominating (76.0%). Consumption follows a “basic needs + entertainment” pattern. Social media recommendations (61.5%) and peer interaction (52.1%) strongly shape decisions. Monthly spending is right-skewed (skewness = 1.68, mean = 847 yuan, median = 750, SD = 282). Daily usage time correlates moderately with spending (r = 0.56, P < 0.01). Social media guides consumption via algorithmic pushes, influencer marketing, and peer comparison, contributing to irrational consumption and low financial literacy. Targeted suggestions are provided for schools, families, society, and individuals to foster rational consumption and improve financial literacy.