Filter membrane in heavy metal Cr element thin film method X-ray fluorescence (XRF) spectroscopy analysis is studied. The results show that Cr element preconcentrated on hydrophilic polytebrafluoroe thylene (PTFE) membranes has good uniformity, and XRF spectroscopy detection of Cr element preconcentrated on these membranes has good sensitivity. Different mass concentrations of Cr element are preconcentrated by using hydrophilic PTFE membranes and measured by XRF spectroscopy. The results show that when area concentration of Cr element is in the range of 3.84~167 μg·cm-2, the fluorescence integrated intensity of Cr Kα characteristic spectral line has a very good linear relationship with the area concentration of Cr element. The linear correlation coefficient is 0.996, and the limit of detection is 0.3 μg·cm-2. The spiked recovery experiments on tap water samples of laboratory faucet are carried out. The obtained recoveries are between 93.85% and 101.95%, and the relative standard deviation is less than 2%. As a result, the thin film method XRF spectroscopy analysis with hydrophilic PTFE membrane as preconcentrated filter membrane can be well applied to the analysis and detection of heavy metal Cr element in water samples.