Li Jishun was convicted of having “raped or sexually abused” 26 girls aged from 4 to 11, the official Xinhua news agency said.
The abuse took place in 2011 and 2012, when he was a teacher at a primary school, it added.
Li was put to death on Thursday by a court in Tianshui, in the northwestern province of Gansu, Xinhua said, adding that he was handed the heaviest punishment possible because of the harm caused to the children and the “extremely negative social impact” of the case.
“He took advantage of those who were both childish and timid and committed his acts in dormitories or classrooms,” Xinhua added.
It cited China’s Supreme People’s Court as saying child sexual abuse cases have risen in recent years, with 7,145 across the country in the 2012-2014 period.