Chanting of a mantra is the perfect way of awakening the consciousness within and can demonstrate a therapeutic effect on the body. The most important mantra for the Tibetian Buddhists associated with the bodhisattva – Avalokiteśvara is the six - syllable mantra Oṃ Maṇi Padme Hūṃ. In Tibetan Buddhism, in particular, the Kāraṇḍavyūha Sūtra is one of the most significant texts, because it is the source from which the syllable “Oṃ Maṇipadme Hūṃ” is derived. This mantra originated in India and it is in Sanskrit. Oṃ Maṇi Padme Hūṃ is the most widely used of all Buddhist mantras. It is open to anyone who feels inspired to practice it to develop great love and compassion. On the other hand, the Oṃ Namaḥ Śivāya mantra is a five syllable mantra that is associated with the qualities of grace, truthfulness and love. Oṃ Namaḥ Śivāya mantra is perhaps among the most powerful and the most popular mantras on the earth. Also called as the Pañcākṣara or Pañcākṣarī mantra, we find the five syllabled mantras Namaśivāya (Na + Ma + Śi + Vā + Ya) attributed to Lord Śiva and affixed with ‘Oṃ’, the primordial sound. Oṃ Namaḥ Śivāya is a most potent and popular mantra, which is at the heart of the Vedas, Purāṇas and Tantra. In Hindu tradition, Lord Śiva was considered as lord of meditation, who enlightens the universe. This study is a comparison of two well-known mantras – Oṃ Maṇi Padme Hūṃ; a Tibetian Buddhist mantra and Oṃ Namaḥ Śivāya; a Hindu mantra.