As the capital of Arunachal Pradesh, Itanagar is the seat of the state government. It houses the Arunachal Pradesh Legislative Assembly, the Secretariat, and the Raj Bhavan (the official residence of the Governor).
At the local level, civic administration is managed by the Itanagar Municipal Corporation (IMC), which was established to oversee urban planning, sanitation, water supply, and waste management. The city is part of the Itanagar Assembly constituency, which elects a representative to the state legislature. Administratively, the Capital Complex functions as its own distinct district-level entity, headed by a Deputy Commissioner, separating its direct governance from the surrounding Papum Pare district.