Voting in the ballot will take place in the party's offices across Lithuania on Monday and Tuesday, with the results expected on Wednesday.
Candidates for the post include the party's incumbent leader, ex-PM Andrius Kubilius, former leader MEP Vytautas Landsbergis and MP Valentinas Stundys.
Some 16,307 members of the party are eligible to elect the Conservatives' leader.
Under the party's bylaws, the chairman is elected for a two-year term.
