Gandhi criticised the CPI-M, the main opposition in Kerala.
"The CPI-M has no role in national politics, so a vote here for the CPI-M means it would be helping the BJP," said Gandhi.
Gandhi arrived here from Mangalore in a helicopter.
Despite the heat, over 10,000 people waited for him for a few hours.
Chief Minister Oommen Chandy, state party chief V M Sudheeran and T Siddique, the Congress candidate for the Kasargode Lok Sabha seat, accompanied him.
Most of Gandhi's speech was spent on slamming the CPI-M.
"In politics and in democracy there should be no place for violence," he said.
Twenty seats in Kerala go to the Lok Sabha electon on April 10.
For a society to go forward, there should be a balance between prosperity and fairness and "the Congress and its leaders have been doing this over the years in the way it should be done", said Gandhi.
Gandhi has three more meetings. He travels to Idukki and Chenganniur and he finishes his day's last meeting in the capital district constituency at Attingal, after which he returns to Delhi.
Kerala goes to the polls to elect 20 members to the Lok Sabha April 10.