The victim, identified as Sharda S. Ghodeswar, was on a morning walk near the Golden Club in Chembur when the accident occurred.
She was rushed to the nearby Shatabdi Hospital but declared dead on arrival, said the official.
This is the second such incident in Chembur in the past six months.
On July 20, Kanchan Nath was killed when a tree suddenly fell on her at Swastik Park.
In the first incident after the Mumbai Police declined to book the BMC officials for negligence, her husband Rajat Nath filed a criminal writ petition in the Bombay High Court which is expected to come up for hearing soon.
Several activists have said that many fully grown and healthy trees collapse during the monsoon season when they are weakened by heavy winds and rain.
A resident said that during the building of roads, BMC workers and contractors cover up the entire base of all the trees growing besides the roads and highways in the city.
“This does not leave space for the water to seep to the roots, and the trees can’t breathe properly. So although they appear strong and healthy, they can’t withstand heavy rain or winds and suddenly come crashing down with fatal consequences.”
He urged the BMC officials to immediately clear an area of at least one square metre at the base of all trees which are covered by concrete to enable the trees to drink and breathe and remain standing strong and safe without endangering pedestrians and property.