The aim of this study was to evaluate the application value of SPECT/PET (18)F-FDG imaging in patients with lymphoma and its significance in monitoring relapse of this disease. A retrospective analysis of 71 SPECT/PET examinations was performed in patients with lymphoma diagnosed by pathologic and immunohistochemistry means from 1998 to 2008 in Peking university first hospital. The results showed that 28 patients underwent SPECT/PET before initial therapy, the accuracy of SPECT/PET and CT were 100% and 81.7% respectively. The diagnostic sensitivity of SPECT/PET and CT for foci were 85.7% and 53.5% respectively, and there was significant difference between them (p = 0.003). The diagnostic sensitivity of SPECT/PET and CT for extranodal foci were 91.3% and 56.5% respectively, there was significant difference also between them (p = 0.007). 32 patients underwent 43 SPECT/PET for monitoring relapse during follow up. The positive predictive value and negative predictive value of SPECT/PET for relapse were 100% and 92.9% respectively. The relapse were found by SPECT/PET in 6 patients more early than appearance of clinical symptoms and physical signs as well as laboratory examination, imaging examination. In conclusion, SPECT/PET has significant value in diagnosing and monitoring relapse for patients with lymphoma.