The 51-year-old woman was rushed to hospital in a critical condition following the smash at a busy junction on The Broadway, Ealing.
The incident at about 1.30pm on Thursday, October 12 left her with serious injuries.
Surgeons battled to save her but she died a week later on Thursday, October 19 at 11.45pm, police said.
Harrowing images posted on social media on the day of the crash showed emergency services at the scene and a blue bicycle mangled in the road.
A large police cordon was put in place for several hours as a police investigation was carried out.
The lorry driver stopped at the scene and was not arrested, Scotland Yard said.
Detective Sergeant Cheryl Frost of the Met's SCIU said: "This incident took place in a busy area at a heavy footfall time of day.
“I am confident that a number of people must have seen what happened.
"I urge anyone who has information to contact police without delay."
The woman’s next of kin have been informed and a post-mortem examination will be held in due course.
Anyone who witnessed the collision or has any information should call the Alperton Traffic Garage witness line on 0208 991 9555 or Crimestoppers on 0800 555 111.
