Objective To study the expression and significances of Toll like receptors (TLRs) in human high invasive breast cancer cells MDA-MB-231 and poor invasive breast cancer cells MCF-7. Methods TLRs mRNA expression levels were detected in breast cancer cell lines MDA-MB-231 and MCF-7 by reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR. TLRs protein expression levels were detected by flow cytometry (FCM) and immunofluorescence methods. Results Human breast cancer cell lines MDA-MB-231 and MCF-7 expressed TLRs including TLR1-TLR10 at both mRNA and protein levels. The mRNA expression of TLR4, TLR6, TLR8 and TLR9 in MDA-MB-231 cells was obviously higher than that in MCF-7 cells respectively, and the expression in MDA-MB-231 cells was (39.4 ±3. 2),(10. 8 ± 2. 4), (5. 8 ± 2. 6 ) and (3. 2 ± 2. 5) times as much as that in MCF-7 cells respectively ( P ＜0. 01). Protein expression of TLR4, TLR6, TLR7 and TLR5 in MDA-MB-231 cells was significantly higher than that in MCF-7 cells respectively, and the expression in MDA-MB-231 cells was (6.4 ± 1.6),(4. 1 ± 0. 9), (3. 7 ± 0. 8 ) and (2. 8 ± 0.4) times as much as that in MCF-7 cells respectively ( P ＜0. 01). Conclusion TLR1-TLR10 was expressed widely and differentially in human breast cancer cell lines MDA-MB-231 and MCF-7. TLR4 mRNA and protein levels were the highest out of TLR1-TLR10.The differential expressions of TLRs may be related to the invasion capacity of human breast cancer cells.TLR4 may provide basement for breast cancer target gene therapy.