Australia's competition watchdog has launched a major lawsuit against the construction union and its senior officials over an alleged $10 million boycott of concrete company Boral.

The embattled Construction, Forestry, Mining and Energy Union is alleged to have masterminded a secondary boycott of Boral's products that froze the company out of almost all high-rise work in Melbourne. Senior union officials including state secretary John Setka and assistant secretary Shaun Reardon are named in the lawsuit as alleged leaders of the boycott.

CFMEU Victorian state secretary John Setka has been named in a lawsuit launched by the competition watchdog.

The fresh court action will increase pressure on Victorian Labor leader Daniel Andrews ahead of the coming state election. The Napthine government has repeatedly attacked Mr Andrews for factional links to the CFMEU and Mr Setka.

Documents filed in the Federal Court by the Australian Competition and Consumer Commission on Thursday allege the CFMEU instructed its shop stewards to tell Boral customers on 12 worksites that the company's concrete was not permitted.