"Peter was an industrial leader of the highest integrity and his passing is a sad loss to New Zealand."
John Bishop of the Taxpayers' Unions described him as "an unfailingly honourable and dedicated New Zealander who strove to serve the people he represented".
Their tributes followed those yesterday from the leaders of the Labour and Green parties.
Labour leader Andrew Little, a former union leader, was a personal friend of Mr Conway's.
"I will miss him greatly, as will all of those who knew him well, and who share his belief in a better and fairer society," Mr Little said.
Mr Conway joined the CTU in 2000 as the economist and director of policy. He was elected CTU secretary in 2009.
His family issued a statement yesterday saying he had battled a depressive illness for a year.
"Peter fought hard in a daily struggle to stay with the family he loved. He carried this terrible illness with the same dignity and kindness that he lived his life, but ultimately it took him."
Mr Conway is survived by his wife, Liz Riddiford, and three children, Maddy, Sean and Rosa.