Objective： To observe the clinical curative effect of modified Maxing Shigan tang for community acquired pneumonia(CAP)in adults with phlegm-heat in lung syndrome.Methods：One hundred and ten cases of adults with CAP of phlegm-heat in lung syndrome were included in the study and were divided into the control group and the observation group according to the random number table method，55 cases in each group.Observed the changes of c-reactive protein(CRP)，neutrophils granulocyte rate(GR)，white Blood cell count(WBC)，immunoglobulin(IgG，IgA，IgM)，and CD4+/CD8+in both groups before and after treatment，recorded the disappearance time of main symptoms，and compared the total effective rate and incidence of adverse reaction in both groups.Results：After treatment，the levels of CRP，GR，and WBC in both groups were all reduced(P＜ 0.05)；the three indexes in the observation group were all lower than those in the control group(P＜ 0.05).After treatment，the levels of IgG，IgA，and IgM and CD4+/CD8+in the observation group were higher than those before treatment and those in the control group in the same period(P＜0.05).Compared IgM levels of the control group after treatment with that before treatment，the difference was not significant(P ＞ 0.05).The total effective rate was 94.55%in the observation group and 78.18%in the control group，the difference being significant(P＜0.05).The time for improvement of cough，expectoration and fever in the observation group were all shorter than those in the control group(P＜0.05).There was no significant difference in incidence of adverse reaction between the two groups(P＞0.05).Conclusion：Based on routine therapy，the additional application of Maxing Shigan tang for community acquired pneumonia in adults with phlegm-heat in lung syndrome can reduce level of inflammatory factor，improve clinical symptoms，strengthen the immune function，and develop the curative effect.