The 51-year-old man was arrested at an address in Hackney shortly after 4am on Monday, 11 January. He has been taken into custody.
A murder investigation was launched on Sunday, 10 January after police were called to a residential address on Tavistock Gardens in Ilford, at 4.24am to reports of a disturbance.
Officers attended along with paramedics from the London Ambulance Service.
Two men, aged 43 and 45, were found with stab injuries.
Despite the efforts of emergency services, they were both pronounced dead at the scene.
Officers believe they know the identity of the deceased and are working to inform next of kin.
A 28-year-old woman was also found injured. She was arrested at the scene on suspicion of murder. A Taser was discharged during the arrest.
She was taken to hospital for treatment to her injuries and then taken into police custody; she has been released under investigation
Homicide detectives in the Met’s Specialist Crime Command are investigating.
They are working to understand the full circumstances, including how the parties were known to each other.
A crime scene remains in place.
Detective Chief Inspector Perry Benton, said: “We are keen to hear from anyone who was in the Tavistock Gardens area in the early hours of Sunday, 10 January, who hasn’t already spoken to police.
“We have made two arrests as part of a fast-paced investigation that is piecing together the circumstances of how the two men died.
“We need to hear from anybody who knew these men or anything about the sequence of events that led to their untimely deaths.”
Anyone who has information that could assist police should call the incident room on 020 8345 1570.
Alternatively, call 101 or tweet @MetCC ref CAD 1027/10 Jan.
To remain 100% anonymous contact the independent charity Crimestoppers on 0800 555 111.