The emergency services were called to a home in Pickard Gardens just before 1.30pm on Wednesday (April 30).
Officers rushed to the scene along with the air ambulance and paramedics found the 20-year-old man with stab wounds.
Despite attempts to save his life, he died at the scene.
His family have been told and are being helped by specially trained police officers while formal identification and a post-mortem are awaited.
A 17-year-old and a 25-year-old woman were also taken to hospital.
The teenager was later arrested on suspicion of murder and remains in custody.
An update is expected on the medical condition of the woman.
A spokesperson for the Metropolitan Police Service said: “Detectives are investigating the circumstances of a fatal stabbing in Mile End.
“On Wednesday, 30 April at 13:28hrs police were called to an address in Pickard Gardens, E3 following reports of a stabbing.
“Officers attended the scene alongside the London Ambulance Service and the London Air Ambulance, who treated a 20-year-old man for stab injuries.
“Sadly, despite their best efforts, he was pronounced dead at the scene. A post-mortem examination will be held in due course.
“The man’s family have been informed and are being supported by specially trained family liaison officers. We await formal identification.
“A 17-year-old boy was taken to hospital for injuries.
“He was later arrested on suspicion of murder and remains in custody.
“A 25-year old woman was also taken to hospital. We await an update on her condition.”
