This paper studies identification method for restriction parameter and deformation parameter of membrane for single-action membrane-type restrictors. A worktable mounting on open-type hydrostatic bearing is designed for the calibrations and the measurements of the inlet pressure, the outlet pressure, and flow rate for the restrictors. Solving combined equations due to minimizing the difference between measured flow and identified flow gives restrictor parameters. Further, the method of least square error is used to regress the polynomials coefficients of supplied pressures.