The Cook Islands opposition Democratic Party says parliament should be convened more often if MPs want to be paid more.
Last week, the Cook Islands News reported Finance Minister Mark Brown saying MPs deserved a pay increase because they hadn't had one for 14 years.
But parliament, which rarely meets, has sat for just three half days so far this year.
Democrats leader Tina Browne said the proposed raise of 45 percent is hard to justiify.
"Because in the last eight years they would meet maybe five days a year, 12 days a year, 15 days, at the most, a year or two days a year. So as it turns out the increase is about 45 percent of the current Members of Parliament's wages."
Tina Browne said the increasing minimum wage is a bigger focus for the opposition.
She said while the government has increased it by 34 cents to an hourly rate of $NZ7.60, the Democrats want to lift it to $NZ10 an hour to more fairly represent the increase in the cost of living.