By combining cultural symbolism with practical value, the marine character intellectual property (MCIP) created from regional maritime resources is increasingly recognized as a strategic asset for coastal communities. In this study, we investigated three representative South Korean cases—Dokdo Guard Kangchi in Ulleung County, HOBOT in Yeongdeok County, and Padossi in Pohang City—to understand their contributions to regional identity, community engagement, and sustainable development. A qualitative approach was adopted, integrating a literature review and multicriteria case studies, with selection criteria emphasizing cultural and educational values, creativity and innovation, community engagement, and long-term viability. MCIP acts as symbolic capital, transforming local heritage, ecological values, and community narratives into accessible forms through media, merchandise, and public initiatives; it enhances environmental literacy (particularly among children and adolescents) by embedding ecological themes in culturally resonant storytelling. Simultaneously, it stimulates the local economy by attracting tourists, generating licensing opportunities, and strengthening regional brand recognition. Such IP fosters cultural resilience, promotes ecological stewardship, and creates scalable opportunities for global dissemination. In sum, MCIP represents an effective model for integrating cultural heritage into the contemporary content industry, offering coastal communities a sustainable pathway to preserve their identities while engaging with both domestic and international audiences.