Mao was rushed to Oking hospital in Kohima for emergency medical treatment, but died after severe internal bleeding, a family member said.
Mao had been a journalist since 1995. He began his career with The Shillong Times in Meghalaya, then moved to Nagaland and worked with the Asian Age and later joined Nagaland Post.
Condoling the demise of Mao, Nagaland Chief Minister Neiphiu Rio said: "Daiho Mao was a hardworking journalist who dedicated his life to journalism. He had a bright future which has been cut short due to his sudden demise. His sudden departure is not only a personal loss to the family, but to the state as a whole."
Representational picture of beehive
Rio also sent his heartfelt condolences to the members of the bereaved family and to his numerous friends, associates and admirers.
Expressing grief at the death of Mao, former Maharashtra and Goa Governor S.C. Jamir said his sudden demise has caused irreparable loss to the media fraternity in the state.
"Mao was a hardworking person and a successful journalist," Jamir said in his condolence message.
The journalist fraternity in Nagaland got together to offer condolences on the death of Mao, whose funeral will take place in his native village at Shajouba in Manipur Monday.