A group of people claiming to be dissident Congressmen ransacked the party office here Wednesday, saying they were upset over the distribution of tickets for the general election.
The attackers burnt party posters, damaged furniture and smashed signboards.
An effigy of state Congress president and former chief minister J.B. Patnaik was also burnt.
The protesters raised slogans against the ticket given to former assembly speaker Sarat Kumar Kar, who had joined the Congress in March after being denied re-nomination by the ruling Biju Janata Dal (BJD) supremo Naveen Patnaik.
Kar filed his nomination for Bhubaneswar assembly seat on Wednesday.
More than two dozen BJD leaders have joined the Congress in the past one month and many have been given the party ticket.
Orissa will witness simultaneous elections for 21 Lok Sabha and 147 assembly seats.