The CFMEU has been fined $132,000 over breaches of industrial law at construction sites across Adelaide.
The Federal Court handed down several judgments against the CFMEU over offences committed at three worksites between April and June 2014.
Five officials, including SA secretary Aaron Cartledge and assistant secretary Mick McDermott, were found to have unlawfully entered building sites without permits to speak to workers.
The union was fined a total of $110,000, while officials shared in fines of $22,000.
Justice Berna Collier said the breaches were at the lower end of the scale of seriousness.
But she described the union as a "repeat offender" which had shown indifference to industrial laws.
"Penalties imposed on the union appear to have no impact," she said.
"The obvious inference to be drawn is that the CFMEU has ignored such penalties as inconsequential."
Justice Collier noted that while there was no suggestion of aggressive or threatening behaviour, each of the officials had previously breached industrial laws.
The CFMEU and more than a dozen of its officials were fined almost $1 million in April over similar breaches at building sites across Adelaide between October 2013 and May 2014.