Seven other people were also injured in the attack in the city of Kaiyuan, in Liaoning province, state television station CCTV said.
A single suspect, surnamed Yang, has been arrested and police are investigating the case, the Kaiyuan municipal public security agency said in a statement.
The police did not mention the reason for the attack, nor details about the suspect or the victims. CCTV said a police officer who helped subdue the suspect was among the wounded.
A video posted by the state-run Beijing News on Chinese social media showed two policemen – one of them wielding a broom – confronting the suspect and knocking him to the ground.
Public knife attacks are not uncommon in China.
In June, 37 children and two adults were injured by a knife attacker at an elementary school in southwest Guangxi.
In October 2018, a woman wielding a kitchen knife cut at least 14 children in a kindergarten in central Chongqing.
Nine students were killed at a secondary school in Shaanxi province in April 2018 by a 28-year-old man who was later sentenced to death.
In 2017, 11 students were injured after a man climbed the wall of a kindergarten with a knife and started attacking them.
But perhaps the worst wave of stabbings occurred in 2010, which included a period of three consecutive days when attackers attacked schools. China’s Ministry of Education responded to these events by ordering schools to strengthen security and prevent outsiders from entering campuses.