ObjectiveTo evaluate the clinical efficacy of Qimai Qinlou prescription in the treatment of elderly community-acquired pneumonia （CAP） （non-severe） with Qi and Yin deficiency and phlegm-heat obstructing lung syndrome and its impact on immune-inflammatory factors. MethodA total of 120 eligible patients were randomly divided into an observation group （60 cases） and a control group （60 cases）. Both groups received intravenous cefoxitin sodium. In addition， the observation group received oral Qimai Qinlou prescription， while the control group received an oral placebo simulating Qimai Qinlou prescription. The treatment course was 14 days. The disappearance time of major clinical symptoms and signs was recorded. Traditional Chinese medicine （TCM） syndrome scores and the Clinical Research Outcome （CAP-CRO） scale scores for pneumonia of the two groups were compared. Chest computed tomography （CT） scans were performed， and peripheral blood levels of procalcitonin （PCT）， interleukin-6 （IL-6）， serum amyloid A （SAA）， high-sensitivity C-reactive protein （hs-CRP）， CD4⁺， CD8⁺， and CD4⁺/CD8⁺ were measured. The conversion rate to severe condition during hospitalization， readmission rate within 30 days after discharge， and safety evaluation were recorded. ResultAfter treatment， the observation group showed significantly shorter time of fever， cough， expectoration， and disappearance time of lung moist rales than the control group （P<0.01）. The TCM syndrome scores， CAP-CRO scores in all dimensions， and total scores in both groups were significantly reduced as compared with those before treatment （P<0.01）. After treatment， the observation group had a more significant reduction than the control group （P<0.01）. The levels of PCT， IL-6， SAA， and hs-CRP in both groups were significantly reduced as compared with those before treatment （P<0.01）. After treatment， the observation group showed a more significant reduction than the control group （P<0.01）. There was no statistically significant difference in the changes of CD4⁺， CD8⁺， and CD4⁺/CD8⁺ in the control group before and after treatment. However， in the observation group， CD4⁺ and CD4⁺/CD8⁺ levels significantly increased （P<0.01）， while CD8⁺ level significantly decreased （P<0.01） after treatment. After treatment， CD4⁺ and CD4⁺/CD8⁺ in the observation group significantly increased （P<0.01）， and CD8⁺ significantly decreased as compared with those in the control group （P<0.01）. At 7， 10， and 14 days after treatment， the curative rates in the observation group were 53.33% （32/60）， 85.00% （51/60）， and 91.67% （55/60）， respectively， which were higher than 31.67% （19/60）， 61.67% （37/60）， and 68.33% （41/60） in the control group （χ²=5.763， 8.352， 10.208， P<0.05）. After treatment， the total effective rate of CT scanning in the observation group was 93.33% （56/60）， higher than 80.00% （48/60） in the control group （χ²=4.615， P<0.05）. The conversion rate to severe condition during hospitalization in the observation group was 3.33% （2/60）， lower than 15.00% （9/60） in the control group （χ²=4.904， P<0.05）. The readmission rate within 30 days after discharge in the observation group was 8.33% （5/60）， lower than 23.33% （14/60） in the control group （χ²=5.065， P<0.05）. No serious adverse drug reactions were observed in either group during the treatment period. ConclusionQimai Qinlou prescription can enhance immune function， alleviate inflammatory reactions， significantly relieve clinical symptoms， shorten the duration of the disease， improve the curative rate and CT scanning efficacy， prevent disease progression， reduce the readmission rate in the short term， and is clinically safe for the treatment of elderly patients with non-severe CAP with Qi and Yin deficiency and phlegm-heat obstructing lung syndrome. It is worthy of further research and application.