It was the second in the city against Government plans to allow employers to sack workers without reason or explanation within the first 90 days of employment; restrict access to workplaces for unions; and force workers to produce medical certificates for every day they are unwell.
Council of Unions Otago convener Glenda Alexander was pleased with the turnout, which represented a wide range of occupations, political views and ages.
"The main thrust was that anything which will compromise or reduce workers' rights is not a runner," she said.
The group passed a resolution opposing the proposed changes and calling on the Government to "desist in this course of action and recognise that workers have a right to be treated with fairness at work".
"People are seeing that this is not just about the unions, but it's about all workers and democracy."
An unplanned march also occurred when about 150 protesters walked up Stuart St chanting.
Before they were able to reach the Octagon, where the HMNZS Otago charter parade was taking place, Inspector Dave Campbell, who was attending the parade, intervened and moved them down Bath St.
From there the group marched along George St, disrupting a small amount of traffic, before returning to the Octagon after the Navy parade had finished.
Mrs Alexander acknowledged the right of the Navy to not have their event disrupted and appreciated the tolerance shown to the group.
"We need to respect that as well and it was not an approved or sanctioned march, but I guess it was just the enthusiasm of the people to carry on protesting."
The issue of obtaining permission to march on the street would be discussed in relation to other events, she said.
The Council of Trade Unions is planning a "national day of action" for mid-August, which will include protest rallies and marches.
