Rahul Gandhi was staying in the hotel before his departure to Rameswaram to attend the funeral ceeremony of foremer President A P J Abdul Kalam.
Police said Radhakrishnan (52) was asking a motorbike rider to take diversion when the rider lost control of the vehicle and hit him.
The police official who was seriously injured was admitted to a private hospital where he died.
The bike riders Sheik Abdullah and Kadher Oli Beer Mohammed also were injured in the accident and had been admitted to a hospital, police said.