The boy, a French national who was visiting London with his family, was hospitalized for his injuries after falling five storeys and remains in a stable but critical condition, London's Metropolitan Police said.
The alleged assailant will later on Tuesday appear before Bromley Youth Court, police added.
"A 17-year-old male arrested on Sunday after a boy aged six was seriously injured at the Tate Modern has been charged with attempted murder," the police statement said.
"Police are continuing to appeal for further witnesses to come forward."
Emergency services were called to the scene on Sunday afternoon after the young boy fell from the viewing platform, which is located on the 10th floor of one of London's most popular tourist attractions.
He was found on the museum's terrace, which is on the fifth floor, and was airlifted to a London hospital.
The Tate Modern temporarily closed the gallery following as police investigated the incident.
It later reopened the gallery but the viewing platform remains closed.
Police said there was no link between the suspect and the victim.
The Tate Modern opened in the disused power station on the River Thames in 2000.
It was the UK's most popular tourist attraction in 2018 with 5.9 million visitors, according to the Association of Leading Visitor Attractions.
( With inputs from IANS )