Congress MLA from Jhalod in Gujarat's Dahod district Bhavesh Katara resigned as a legislator on Wednesday night.
He is the third Congress MLA to resign in the last two days, after Mohansinh Rathwa and Bhagwan Barad.
Katara went to the residence of assembly Speaker Nimaben Acharya and submitted his resignation to her, an official statement said.
His resignation comes at a time when the BJP is finalising candidates for the Gujarat Assembly elections. Katara is likely to join the BJP on Thursday.
Earlier, Rathwa and Barad also joined the saffron party after resigning from the Congress party and as MLAs.
Gujarat elections will be held in two phases on December 1 and December 5, and counting of votes will be held on December 8.