Objective To investigate the mosquito infestations in different schools in the central urban area of Shanghai, China and to assess the risk of mosquito-borne diseases among the students. Methods Five nurseries,4 primary schools, and 3 secondary schools in Huangpu district of Shanghai were randomly selected for investigation. The mosquito infestations in the nurseries and schools in June and August 2012 were evaluated by investigation of mosquito breeding sites and human-baited trapping. Results The mean densities of Aedes albopictus in nurseries, primary schools, and secondary schools were significantly higher in August than in June (0.25 vs. 0 mosquito/30 min·monitoring point; 3.67 vs. 0.92 mosquitoes/30 min·monitoring point; 0.11 vs. 0.06 mosquito/30 min·monitoring point, with over 100% increases when comparing the former with the latter in each pair). In August, the densities of adult mosquitoes in nurseries and primary schools were 0.45 and 3.67 mosquitoes/30 min· monitoring point, respectively; there were also increases in the positive rates of small ponded waters as breeding sites in nurseries and primary and secondary schools (47.1% vs. 16.7%; 34.5% vs. 28.6%), and the positive rate increased significantly in nurseries (χ²=3.970, P=0.046). Conclusion The indices of mosquito infestation and numbers of mosquito breeding sites per school in the central urban area of Shanghai are significantly higher than the local standards, and they show significant increases in summer. It is recommended that the education sector and schools should enhance environmental management in campus and ensure the health of teachers and students.