Neurological and psychiatric problems, such as depression, insomnia, anxiety, Parkinson’s, and Alzheimer’s diseases, are considered huge health challenges all over the world. Conventional therapies are found to be ineffective in some cases owing to resistance development. Moreover, they could elicit a wide range of side effects. Currently, there is increased demand for therapeutically beneficial plant-derived nutraceuticals as natural alternatives to address these conditions. The current chapter explores the effectiveness and therapeutic activity of natural phytometabolites of terrestrial and marine origin, such as Hypericum perforatum, turmeric, and saffron, against a range of disorders. The key neurobiological pathways by which these herbs and compounds exert their actions are stated in this chapter. Notably, the use of these nutraceuticals is associated with critical challenges, as discussed in this chapter, including regulatory obstacles, safety concerns, and bioavailability issues. This comprehensive chapter emphasizes the role of herbal nutraceuticals as a promising and valuable component in the development of sustainable strategies for mental and neurological health.