In the video, the soldier was seen putting a headlock on the child while women pull on the soldier's back, in an attempt to make boy free from his clutch.
The incident took place during a weekly protest Friday organized by Palestinian activists against settlement construction in the village of Nabi Saleh in the West Bank.
The family routinely films its demonstrations, said Tamimi, and posts them on a site called Nabi Saleh Solidarity.
"This is very difficult for any father or mother to see their son or daughter in that way, being violently attacked," said Tamimi.
In the video, Bassem Tamimi's daughter, A'hed, is seen biting the soldier's right hand in an apparent attempt to free her brother.
The Israeli army defended its actions, saying that people in the crowd had thrown rocks at the soldiers.