The Rail and Maritime Transport Union is angry Lyttelton Port's chief executive is to get a pay rise of nearly $200,000 despite three deaths occurring on site since December.
Peter Davie's salary has jumped from $1.04 million in 2013 to $1.24 million this year.
The union's South Island organiser, John Kerr, said today the 18 percent pay rise was unjustified and inflammatory.
Mr Kerr said the success the port had seen in the past 12 months was down to port workers doing difficult and dangerous jobs around the clock.
The Canterbury port had an appalling health and safety record, with three workers killed in the past 12 months, he said.
Lyttelton Port's annual report for 2014 shows the company achieved a net profit, after tax, of $343.2 million - an increase of 1929% on the previous year.
It settled almost $440 million in insurance claims in December last year.