The attacker, who was armed with a knife, burst into the unnamed kindergarten in Shandong's Zibo city Tuesday afternoon, the Hong Kong-based Information Centre for Human Rights and Democracy quoted a local police official as saying.
The attacker later surrendered to police, Hong Kong newspaper Ming Pao reported.
Chinese state media did not immediately report the incident, which is the latest in a series of attacks at schools and kindergartens in China this year.
At least five similar attacks have been reported, resulting in the death of dozens of children and several teachers.
Following the earlier attacks, the government ordered a review of security at schools, while state media have discussed possible underlying causes of the attacks.
"Apart from adopting forceful security measures, we also need to focus on addressing some deep-rooted causes behind these problems, including handling some social contradictions, resolving disputes and strengthening the role of grassroot mediation," Premier Wen Jiabao told Hong Kong-based Phoenix TV in May.