He was 53 and is survived by his wife and two daughters, family members said.
Pathak had suffered a heart attack on August 14 and was admitted to a local hospital where he breathed his last this morning.
Pathak was serving as the Editor of Hindi daily 'Dainik Purvoday' and was earlier the Executive Editor of 'Purvanchal Prahari'.
A prolific writer in Maithili, Pathak was also a member of Sahitya Akademi's selection committee for Maithili literature.
Assam Chief Minister Tarun Gogoi condoled the death of the senior journalist saying that it was an immense loss to Hindi journalism and the entire media fraternity in the state.