 This study aimed to obtain baseline data on the incidents and cost of community-acquired mnemonia among under five children in three townships from Heilongyang, Hubei, and Gansu Province and one community in Shanghai. The results showed that the overall incidents of clinically diagnosed mnemonia was 2.55% with a higher incidence in urban areas, 7.97%, than rural areas, 1.68%. No difference was found in the incidences of chest x-ray confirmed mnemonia between urban and rural areas. The hospitalization rate of all cases was 1.4%. Incidence and hospitalization rates decreased with age, with the highest rates found among children younger than one year and the lowest among children aged four. The total cost due to mnemonia for the participants was 1,138,733 yuan, with an average cost of 5,722 yuan and a median cost of 3,540 yuan. Multivariate analysis showed that hospitalization was the only factor related to higher cost. The study suggests that further health economics evaluation on introducing pneumococcal conjugate vaccine into the national immunization program should be conducted. This article was authored by Yang Li, Ji Jian, Doping Yin, and others. We are article.tv, links in the description below.