Abstract: Objective To investigate the biodistribution of a new PET tracer—11Cpodophyllotoxin（11C-PDT） in mice model of lung carcinoma and inflammation， and the value of 11C-PDT to differentiate the two models. Methods The biodistribution of 11C-PDT was performed in mice model，and 18F-FDG was used as control. Twelve mice with lung carcinoma and twelve mice with inflammation were divided into two groups according to the different tracers at random. 11C-PDT or 18F-FDG was injected into coccygeal vein of mice model. The biodistribution of mice for 11C-PDT and 18F-FDG were measured with wellgamma detector at 60 min after injection. Results On the biodistribution study of 11C-PDT，the radioactive uptake（%ID/g） in tumor was higher than that in the inflammation tissue（0.63±0.25 vs. 0.29±0.09，P＜0.05）；the radioactive uptake（%ID/g）of 18F-FDG in tumor was also higher than that in the inflammation tissue（7.56±1.77 vs. 3.83±0.71，P＜0.01）. The uptake between 11C-PDT and 18F-FDG in tumor was of significance（P＜0.05）. The ratios of inflammation／muscle of 18F-FDG（1.58±0.11）were higher than those of 11C-PDT（0.73±0.28）with statistic significance（P＜0.05）. Conclusion11C-PDT is more specific than 18F-FDG in tumor tissue, and could be used as PET tracer to differatiate lung carcinoma from inflammation in the future.