Objective: To investigate the relationship among the TNFRp55 and TNFRp75 expression in tumor cell lines in vitro, the suppression of nrhTNF on the tumor cell lines growth and the changing of NF-kB activity in the tumor cell lines. Methods:The expressions of TNFRs are studied by immunohistochemistry. The inhibition of nrhTNF to tumor cells was investigate by crystal violet assay. The changing of activity of NF-icB was evaluated by using immunohistochemistry and Western blot methods. Results: In tumor cell lines, positive rates of expression of TNFRp55 and TNFRp75 were 99% and 98. 8% respectively. There was no significant difference among various types of tumor cells (P>0. 05). nrhTNF could inhibit the growth of SW480, SGC7901, 8910, SMMC7721 and BEL-7402 cell lines in which NF-icB translocated into cytonuclei slightly. However, nrhTNF has no effects on A549, PLA801, Hela, Ecal09 and GRC-1 cell lines in which NF-kB translocated into cytonuclei obviously. Conclusion: The low degree of activating of NF-kB m Objective: To investigate the relationship among the TNFRp55 and TNFRp75 expression in tumor cell lines in vitro, the suppression of nrhTNF on the tumor cell lines growth and the changing of NF-kB activity in the tumor cell lines. Methods: The expressions of TNFRs are studied by immunohistochemistry. The inhibition of nrhTNF to tumor cells was investigated by crystal violet assay. The changing of activity of NF-icB was evaluated by using immunohistochemistry and Western blot methods. Results: In tumor cell lines, positive rates of expression of TNFRp55 and TNFRp75 were 99% and 98.8% respectively. There was no significant difference among various types of tumor cells (P> 0.05). NrhTNF could inhibit the growth of SW480, SGC7901, 8910, SMMC7721 and BEL-7402 cell lines in However, nrhTNF has no effects on A549, PLA801, Hela, Ecal09 and GRC-1 cell lines in which NF-kB translocated into cytonuclei obviously. Conclusion: The low degree of act ivating of NF-kB m