Another person has minor injuries in the incident.
"At about 11.30am Police were called to reports of a stabbing incident, where multiple people were injured," Detective Inspector Scott Beard said.
The stabbing is at a house on The Drive - a major thoroughfare through Epsom.
"Upon Police arrival, two people were located with critical injuries," Beard said.
"First aid was immediately provided, however both have sadly died at the scene. A third person found at the property has been taken to hospital with critical injuries.
"Police are making a number of initial enquiries to establish what exactly has taken place.
St John confirmed paramedics treated two people - one in a critical condition and another in a minor condition.
Both people have been taken to Auckland City Hospital.
A spokeswoman said they received a call at 11.26am asking for help at The Drive.
