Several clinical trials and case series have provided evidence, supporting the use of CoQ10 in the prevention and treatment of various disorders related to oxidative stress. It has been shown that CoQ10’s antioxidant properties and central role in mitochondrial oxidative phosphorylation make it useful as adjunct therapy for cardiovascular diseases such as CHF, hypertension, stable angina, drug-induced cardiotoxicity, and ventricular arrhythmia, and non-cardiac conditions including cancer, periodontal disease, compromised immune systems, COPD, and muscular dystrophy. Therefore, we are advocating its use as a supplement In a prospective randomized double-blind sequential sampling. All patients with community acquired pneumonia(CAP) accidentally referring to two groups. In group A addition to the usual treatment of CAP (based on the infectious diseases society of America guideline), will receive Co- enzyme Q-10 200 mg daily for 14 days, and in Group B, in addition to the usual treatment (based on the infectious diseases society of America guideline), will receive a placebo. As well as the two groups will be matched (GROUP MATCHING) and information of patients in the two groups include demographic data and changes to the clinical symptoms and laboratory (including CBC, ESR, CRP qualiitative, ABG) at the beginning of the third , seventh and fourteen day of therapy will check with the use of a questionnaire, and finally data were analyzed by SpSS using Chi square and Fisher exact test and student test and odds ratio will be doing and the P-value less than 0.05 To be considered significant.