This study examines how entrepreneurs’ public-speaking competence shapes investor sentiment and firm valuation in China’s emerging industries. Drawing on nine cases across digital technology, cryptocurrency, and new energy vehicles, we analyzed narrative structure, emotional marker density, credibility anchors, and delivery dynamics. Findings from this mixed methods study shows that while narrative structure and emotional marker density cues has no significant effect on Investor Sentiment, credibility anchors and delivery dynamics significantly enhance investor sentiment, which mediates their effect on firm valuation change. These results highlight that credibility anchors and delivery dynamics function as the strongest communicative signals, amplifying investor confidence and valuation outcomes. For practitioners, the study underscores the strategic value of cultivating credibility and delivery skills to strengthen market trust and access to capital. By linking communication and entrepreneurial outcomes, this research clarifies how rhetorical competence can be leveraged to support firm growth in competitive environments.