Asked if the Congress will have any alliance for the assembly polls, he answered in the negative.
Mistry said the party's preparations were proceeding well and expressed confidence of coming to power in the southern state where the Bharatiya Janata Party (BJP) has been in power since 2008.
"We will win the polls... Hundred percent," he said.
He said the party will raise local issues during the elections and "expose the misgovernance" of the BJP government.
To a question about projecting a chief ministerial candidate in Karnataka, Mistry said that it was not the practice in Congress.
Party sources said several Congress leaders from the state were desirous of becoming the next chief minister amid speculation that party's fortunes had brightened following troubles faced by the BJP following rebellion of former chief minister B S Yeddyurappa.
The term of the Karnataka assembly will come to an end June 3 this year.