Mr Key understood a hikoi protesting against deep-sea drilling was likely to arrive at the marae at the same time as him and he was aware of plans for another protest.
However, he expected any protests would be short-lived.
"As soon as [the media] pack up and go somewhere else, they go home and actually it's a nice family day at Waitangi and it's actually usually a nice family day around the rest of New Zealand. I think there are lots of New Zealanders who would say why don't we have that all the time."
Mr Key expected Mrs Harawira, mother of Mana Party MP and leader Hone Harawira, to again accompany him onto the marae where he would have two main messages for Maori.
The first was that National had been good for Maori and had delivered very strongly over the last five years. The second point would be around Treaty settlements, particularly those around the Far North.
"There's a settlement on the table now. I know Ngapuhi are very keen to get that settlement over the line. I think in what is one of the poorest parts of the country, it can make a tremendous difference. There's hundreds of millions of dollars that could be used in that economy to really better the Maori people of the Far North so we're going to be really actively encouraging them to settle that deal."
Labour leader David Cunliffe and his colleagues arrive at Te Tii shortly after Mr Key and his ministers.
Mr Cunliffe said in his first visit to Waitangi as Labour leader he was looking forward to "setting a very positive tone in terms of our discussion with Ngapuhi and to continuing it with Maori generally".
He believed Labour's relationship with Maori was moving on from the ill feeling over its foreshore and seabed legislation, which led to Tariana Turia leaving Labour and the formation of the Maori Party.
With Mrs Turia and Maori Affairs Minister Pita Sharples signalling their intention to retire, "I don't think it's any coincidence that there's the opportunity to open a new chapter".
Nine Green Party MPs will be attending, led by co-leader Metiria Turei. NZ First leader Winston Peters will also be there with MPs Tracey Martin and Andrew Williams.
Waitangi events
*John Key will call at Waitangi's Te Tii Marae tomorrow.
*Last year there was a tussle between kuia Titewhai Harawira and Ani Taurua over who would accompany Mr Key onto the marae.
*There is a hikoi protesting against deep sea drilling likely to arrive at the marae at the same time as Mr Key.