Abstract: Objective : To investigate the features of pathomorphology, immunophenotype and molecular genetics and the differential diagnosis of lymphoid tissue tumours of spleen(LTTS). Methods :Paraffin-embedded-section and H E staining were made for morphologic analysis in 4H cases of LTTS,immunophenotype was detected with S-P immunohistochemical(IHC) method and 21 M-Abs in 43 cases, and polymerase chain reaction(PCR)was used to detect IgH and TCR gene rearrangement in 16 cases of primary splenic lymphoma. Results : Of the 43 LTTS, 8 cases (18.6%) were of T cell origin(PTL-N4, HS-TL4), 35 (81.4%) were B cell (HCL13, SMZL5, SLVL2, FL4, MCL2 SLL2, DLBL4, TR-LBL3), and 3 ALLs (autopsy) were not immunotyped. IgH gene rearrangement was found in 8 of 10 cases and T C R gene rearrangement was found in 5 of 6 cases. Mean weight of spleens was 2227.08±324.69g (range from 196g to 6000g). 6 cases were found splenic obstruction. Conclusions : Each type of LTTS may have its unique macrography and histopathology characteristics. It is important to differentiate HCL or ALLs from PLS by PB and BM detections, and to make diagnosis and differential diagnosis of LTTS by PCR and IHC.