Greenpeace's executive director Kumi Naidoo, paid tribute to the late Fernando Pereira, and the rest of the ship's crew, at a ceremony in the port of Gdansk, Poland.
"We honour the entire crew of the Rainbow Warrior which went down, as well as all our folks that work on ships, that take direct action, that hang from coal-fired power plants, that put their lives on the line," he said.
The Rainbow Warrior had been due to lead a flotilla of vessels in a maritime protest against France's Pacific Ocean nuclear tests at Mururoa Atoll.
But shortly before midnight on 10 July, 1985, French agents used underwater mines to blow holes in the Rainbow Warrior’s hull.
Portuguese-Dutch crewman and photographer Pereira, 35, was trapped in his cabin and drowned as a result of the attack.
The operation sparked a severe crisis in France's relations with New Zealand. France denied responsibility initially but acknowledged its involvement in September 1985.
The two agents who had been posing as Swiss tourists and were arrested in the wake of the attack, pleaded guilty to manslaughter and were sentenced to 10 years in jail.
By 1988, however, both were back home in France. A handful of others believed to have been involved were never caught.
Greenpeace is commissioning a Rainbow Warrior Three which is being built in the Polish port, and due for completion in 2011.