Sacred groves, traditional forest fragments preserved by indigenous and local communities, represent invaluable reservoirs of plant diversity. The groves are protected due to cultural, religious, or spiritual beliefs, which have inadvertently contributed to biodiversity conservation. Being a part of forests, these groves are revered as sacred places connected to the local community’s ancestral and spiritual beliefs and have been conserved through generations due to their spiritual and cultural importance. The intrinsic value of these groves lies in their rich biodiversity, harboring diverse plant species, among which few are rare, endangered, or endemic. They are significant reservoirs of plant diversity and a treasure trove of species, which includes rare, endemic, and medicinal plants. They exhibit unique biological diversity and ecological traits according to geographical location, resulting in varied species richness with a wide range of species, such as trees, shrubs, herbs, climbers, epiphytes, parasites, and wild varieties of cultivated plant species. Although there is no comprehensive nationwide study, yet ~13,270 existing records of sacred groves have been chronicled thus far. These areas often remain undisturbed by human activity, allowing for preservation of natural ecosystems and continuation of ecological processes. By analyzing various sacred groves across different regions, the present chapter highlights the unique species compositions, endemic, and rare plants, and the ecological services provided by these ecosystems.