<p>With the popularity of short videos, the performance of online celebrities have garnered significant interest among scholars. However, previous antecedent research on consumer behavior in social media has rarely focused on consumers’ real-time cognitive and emotional processes when faced with different performances of online celebrities. This study used EEG (electroencephalography) signals to calculate four neural engagement indexes—emotion, relaxation, attention, and cognitive load—and explored how online celebrities’ displaying styles and selling approaches affect consumers’ neural engagement in short video advertisements. The experimental results indicated that the transaction-based selling approach and high-displaying style of online celebrities evoked more neural engagement than the relationship-based selling approach and low-displaying style, respectively. Different product types and consumers’ short video addiction degrees made the neural engagement indexes significantly different. These findings broadened the potential applications of EEG and enhanced the literature on consumers’ neural engagement by fusing psychology with short video e-commerce.</p>