A police spokeswoman told The New Zealand Herald the person died after a medical event while on the crossing, with emergency services alerted about 8.38am today.
It comes just over a month after a 75-year-old German tourist died on the walk.
Ngāti Hikairo ki Tongariro and Ngati Tūwharetoa have acknowledged the death and put in place a rāhui for three days, to be lifted at sunrise on Monday.
A rāhui sets a temporary prohibition around an area and limits access for that period in order to acknowledge the death and to express sympathy to the whānau of the deceased, the iwi said in a statement.
"It provides time for tapu (sacredness) to dissipate following the death, and time for healing and recovery of the natural elements at place as well as the people; in particular the grieving whānau."
The rāhui is supported by the Department of Conservation, police and Land Search and Rescue.
To show respect, all hikers in the area are asked to consider using alternative tracks during the period.
