The 21st Public Science Day at the Chinese Academy of Sciences (CAS) commenced under the theme "Navigating the Future with Scientific Inquiries." Across 135 affiliated institutions, nearly 400 engaging science popularization activities were organized, drawing the participation of over 6,000 scientific researchers. Throughout the event, approximately 400 scientific research facilities were opened to the public, welcoming nearly half a million on-site visitors, with the online readership of related topics surpassing 100 million. Wu Zhaohui, Vice President of CAS, graced the main venue, advocating for the integration of diverse science popularization initiatives. The event featured academician-led presentations and roundtable discussions, with over 20 academicians delivering lectures and interactive sessions. Additionally, more than 100 scientific research institutions and universities showcased their "flagship national projects" and key laboratories. A novel AI segment was also introduced, demonstrating cutting-edge technologies like AGIROS and ChipGPT. Online activities, including live streams and quiz challenges, further expanded public engagement avenues.