An investigation was launched after the body of the victim, said to be in her 30s, was discovered at a residential address in City Island Way, E14, shortly after 4pm on Friday.
Officers responding to reports of an assault said the victim was found with a neck injury. She was pronounced dead at the scene.
The Metropolitan Police said the 46-year-old suspect was taken into custody after attending a south London police station on Saturday.
Officials believe the woman was known to the suspect.
A post-mortem examination will be held to determine cause of death and her next of kin has been informed.
Anyone with information concerning this incident that could assist police are asked to call police on 101 quoting CAD 4734/11JAN or Crimestoppers anonymously via 0800 555 111.
The killing brings the number of murders in the capital to seven so far this year. London's homicide toll, which include murders, manslaughters and self-defence killings, for 2018 was 132, a decade high.
Charlotte Huggins, a 33-year-old mother, was London’s first murder of 2019. She was stabbed to death in Camberwell hours after wishing her loved ones a “healthy, happy 2019” on social media.
Michael Rolle, 34, of nearby Dulwich, has been charged with her murder.