Ethical concern from an Auckland University researcher that New Zealand patients may be travelling to China for an organ transplant.

Professor Phillipa Malpas says while Chinese officials have given assurances that organs wouldn't be taken from executed prisoners, that appears to be happening.

She says there's a strong likelihood that a small number of patients will travel from New Zealand to China each year to receive an organ.

Dr Malpas says this has ethical and legal ramifications - particularly for New Zealand health professionals who suspect, or know, their patient is considering procuring an organ from China, or if their patient returns with a transplanted organ.

She's recommending professional medical bodies provide formal guidance for health professionals on this issue.