Police were called at 6.20pm on Monday, 9 August to reports of a disturbance on Churchill Terrace in Chingford.
Officers attended along with the London Ambulance Service and found a 45-year-old man with stab injuries.
Despite the best efforts of officers, paramedics and members of the public, he was pronounced dead at the scene.
His next of kin have been informed and are being supported by specially trained officers.
Detectives from the Met’s Specialist Crime Command are leading the investigation. No arrests have been made.
Detective Inspector John Marriott, said: “A dedicated team of officers are working to piece together the tragic circumstances that led to this man losing his life. The thoughts of all of us are with his family and friends as they come to terms with their loss.
“We have already spoken to a number of key witnesses and recovered CCTV from the area, although I would like to hear from anyone else who witnessed the attack, or a disturbance beforehand.”
Chief Superintendent Richard Tucker, responsible for local policing in Waltham Forest, said: “The Met remains committed to tackling violence across London and I would like to reassure the community that we will do everything we can to track down those responsible for this attack.
“I understand the concern this incident will cause and I would like to reassure residents that you will continue to see additional officers in the area over the coming days. I would urge you to speak with them about any concerns you have.”
A crime scene remains in place.
Anyone who witnessed the incident or has information is asked to call police on 101 or tweet @MetCC quoting reference CAD 5735/09August.