Divided into five volumes, 'Ramayana Mahanveshanam' was first published in 2007 in Kannada. The poem has been translated into English, Hindi, Telegu and Tamil.
Instituted by the K K Birla Foundation in 1991, Saraswati Samman is given annually for an outstanding literary work in any Indian language mentioned in the Schedule VIII of the Constitution. The award carries a cash purse of Rs 10 lakh, a citation and a plaque.
In the poem, Moily tried to explore the 'Ramarajya' or the true principle of the 'ideal State' from a secular and modern point of view, the Foundation said in a release.
His novels 'Kotta' and 'Tembare' have been translated to Hindi, English and many other languages.
The selection for the award was made by a 13-member panel of scholars and writers headed by former Chief Justice of India R C Lahoti.
A rare-politician literary figure, Moily handled many ministries in the previous UPA regime including Petroleum and Natural Gas, Corporate Affairs, Power and Law. He was chief minister of Karnataka from 1992 to 1994.