[ Objective] To apply the nano high performance liquid chromatography coupling with time-of-flight mass spectrometer (nano- HPLC-TOF-MS) to detect the membrane proteins in HaCaT cells. [ Methods] HaCaT cells were collected after the cell confluence reached up to 70% -80% by membrane extraction kit. Then, the enzymatic hydrolysis was conducted on the membrane protein comPlexes, and followed by separation and detection with nano-HPLC-TOF-MS. The identified proteins were classified by bioinformatics analysis. [ Result] There are 9 membrane prote...