He said in a statement after the suspension was announced this afternoon that the move was aimed at silencing him -- the only voice within the party offering genuine and constructive criticism of its relationship with National.
He vowed to continue to raise issues about Maori economic and social disparities both inside and outside the party.
Announcing the suspension, party co-leaders Tariana Turia and Pita Sharples said Mr Harawira had failed to show the restraint and discipline expected of a member and that the caucus had no faith or confidence in him.
"Having no regard for the constitution is one thing. It is quite another to have no regard for the kaupapa and tikanga of the party, and that is really what has brought us to this point," they said.
"Differences of opinion are fine, but they should be addressed within the group."
The suspension would remain in force until further notice.
The move is the latest in an ongoing battle between Mr Harawira and his caucus.
Last month, Maori Party whip Te Ururoa Flavell laid a formal complaint after Mr Harawira wrote in a newspaper column that the party was too wrapped up in its coalition with National and was supporting anti-Maori policies.
A disciplinary committee was due to meet on Wednesday to discuss the complaint.
Mr Harawira sparked further anger in the party at Waitangi celebrations over the weekend, when he gave a "state of the Maori nation" speech an hour before Dr Sharples' own speech.
Mr Harawira has consistently told media he wants to remain in the party, and that he is willing to discuss the points of contention through a kaupapa Maori process to find a resolution.
In his statement, Mr Harawira said he was "hugely disappointed" by the decision to suspend him, adding that it showed disrespect for the kaupapa the party was founded on and the people of his Te Tai Tokerau electorate.
"The decision also shows a complete disregard for the complaint process that the co-leaders were party to, and coming two days out from the disciplinary committee meeting set down to hear the complaint, is also a clumsy and heavy-handed attempt to influence the outcome," he said.
"And yet, for all the contradictions, the decision is also consistent with a pakeha political process which forced Tariana Turia to leave the Labour Party; a process we had decided would never, ever be used in our own party."
Mr Harawira said the decision was aimed at silencing the only voice within the party that had offered genuine and constructive criticism of the relationship with National.
"I can assure everyone, that as long as Maori suffer the economic and social disparities that we do, I will continue to raise those issues both inside and outside of the party."
Mr Harawira said he would attend Parliament tomorrow.
Speaking at a post-cabinet press conference this afternoon, Prime Minister John Key said he did not want to jump to conclusions about the implications Mr Harawira's suspension might have for the Government, but indicated that it could have benefits.
"What action they take is obviously a matter for the Maori Party co-leaders, but, at the end of the day, we have a constructive relationship with the Maori Party and that's a relationship that's based on finding answers to problems and, from what I can see, that's not the space where Hone Harawira's been."
Te Tai Tokerau electorate chairwoman Lisa McNab said electorate executives would meet tonight to discuss the suspension, and that she was unable to comment until then.
Ms McNab said she had not been informed formally by the disciplinary committee as to whether Wednesday's meeting would go ahead.
Mr Flavell told NZPA that as far as he knew the complaint would still be heard on Wednesday.
He would not comment on Mr Harawira's suspension, except to say it was action that had been taken by the party's leadership.
