The unaccompanied child stretched his neck out and became jammed between the moving escalator and the floor, the Xinhua news agency said, citing a publicity official from the capital's Xicheng district.
An investigation had been launched into the tragedy, which happened at around midday at a department store in the Xidan shopping centre.
The incident occurred on a weekend when hundreds of millions of people began returning from the busy Lunar New Year holiday period in China -- a time when people typically hit the shops.
The report did not give more details as to how the young boy got wedged in the escalator.
In July, a 13-year-old boy was killed and over 20 others injured when an escalator in a Beijing underground station suddenly reversed direction during the busy rush hour.