Lei Mingyue, 58, attacked the students, five first-graders and two third-graders, with an axe at around 11:40 AM at an after-school care centrer in Hantai District of Hanzhong City in China's Shaanxi Province, police said.
The students, all from Beiguan Primary School, were waiting in line for lunch when the attack happened, the state- run Xinhua news agency quoted a police officer as saying.
Two passersby were also injured when Lei was running away, he said.
Police later caught Lei, who confessed that he carried out the attack as "revenge on society" following two previous arrests in Beijing and Shaanxi for theft.
Attacks by disgruntled people periodically takes place all over China.
Many targets children as they are soft targets.