"Best wishes to all countrymen on the auspicious occasion of Mahashivaratri. Celebrated as a sacred remembrance of the marriage of Goddess Parvati and Lord Shiva, this festival should be beneficial for the whole of humanity," President Kovind tweeted.
Taking to Twitter, PM Modi said: "Greetings on the special occasion of Mahashivratri. Har Har Mahadev!"
Devotees throng Lord Shiva temples across the country and offered their prayers.
Mahashivratri, also known as the 'Great night of Lord Shiva,' is a Hindu festival observed by devotees from Kashmir to Kanyakumari with much fervour.
It is celebrated on the 14th day of the dark fortnight of the Magha month, as per the Hindu lunar calendar, and marks the night of the marriage of Lord Shiva and Goddess Parvati.