A female cyclist has died almost a week after suffering critical injuries in a truck crash in Sydney's inner west.

Emergency services were called to Parramatta Road at Western Avenue in Camperdown to reports of a crash between a truck and a bicycle just before 4.35pm on March 28.

A cyclist has died almost a week after she was involved in a truck crash on Parramatta Road. Credit:Nine News

The 21-year-old cyclist was treated at the scene by paramedics before she was taken to Royal Prince Alfred Hospital in a critical condition.

Just before midday on Wednesday, the woman's life support was switched off.

The truck driver was not injured in the crash, but was taken to Royal Prince Alfred Hospital for mandatory blood and urine testing.

Police believe the crash occurred when the truck turned left from Western Avenue onto Parramatta Road. The woman had been cycling on Parramatta Road, and a police spokeswoman confirmed she had been wearing a helmet.

Police were investigating the circumstances surrounding the crash, and a report will be prepared for the Coroner.