The northern parts of the state received heavy rainfall, and the major rivers in the region, including the Budhabalanga, Subarnarekha and Baitarani, were in flood, the official said.
Mayurbhanj, Balasore, Keonjhar, Bhadrak and Jajpur districts received incessant rain but Mayurbhanj and Balasore took the brunt of the floods, a senior official in the office of the states' special relief commissioner told IANS.
More than 150 villages in the two worst-hit districts were affected, the official said.
Two people died in Mayurbhanj district Wednesday, in separate incidents, after they tried to cross local rivers.
Nearly 1,000 people, evacuated from their homes after flood waters entered their villages, were being sheltered in nearby schools, the official said.
The state government has alerted the local administration of all the affected five districts, as more rain is expected in the next two days.
District collectors have been directed to take suitable measures. "They have been asked to evacuate people from low-lying areas, if necessary," the official said.