But van der Heyden, speaking on NZME's The Country radio show, said Wilson had done a good job.
"I think that if you ask any dairy farmer in New Zealand - if you ask them if they are happy with a $7.00 milk price - I don't think there will be one who will be unhappy with a $7.00 milk price," van der Heyden said.
However, he said work was needed to improve Fonterra's dividend, which this year will be impacted by the high milk price, writedowns of its investment in China's Beingmate, and the Danone legal settlement.
"I think there needs to be some work done in that area, but if you look at everything in combination, Fonterra has done a really good job - led by John - around the milk price - and the milk price is always going to be 90 per cent of [farmers'] revenue line," he said.
Wilson, who became Fonterra's chairman in 2012, and directors Ashley Waugh and Nicola Shadbolt are due to retire this year by rotation. It will be up to them as to whether they stand again in the co-operative's director elections later this year.
Van der Heyden, who is the current chairman of Rabobank New Zealand, was chairman of Fonterra from 2002 to 2012.