Objective The rich botanical biodiversity resulting from diverse climates and geographical distinctiveness offers a plethora of biological resources that can be pivotal in developing innovative biomaterials. This investigation sought to evaluate the functional properties of indigenous Korean plant species. Methods Forty-six indigenous plants during a year-long expedition across inhabited and uninhabited Korean islands were collected. The plant specimens were divided into 5 parts (flower, fruit, stem, leaf, and whole body) and subjected to extraction using water, 30% ethanol, and 70% ethanol, followed by characterizations of anti-inflammatory, immune response, and anti-bacterial activity. Results Thirty-eight percent of the extracts (59 extracts from 31 species) exhibited statistically significant anti-inflammatory effects. Concurrently, 22% of the extracts (35 extracts from 24 species) demonstrated notable immune boosting effects. Additionally, 17 extracts exhibited significant inhibitory effects against the growth of pathogenic bacteria. Conclusion This study highlights the potential utility of extracts of plants from Korean islands as natural agents for next-generation pharmaceutical and medical applications by emphasizing their effectiveness in combating inflammation, enhancing immune responses, and conferring anti-bacterial benefits.