A high-frequency component test device including a test key and a test module is provided. The test key includes a front-level key and a back-level key which are arranged symmetrically and have the same electrical length and characteristic impedance. The test module is used to measure an S parameter of the front-level key and the back-level key connected directly and an S parameter of a structure where a device under test (DUT) is added between the front-level key and the back-level key. The test module performs S parameter calculation in the frequency domain and converts the S parameter into an ABCD parameter matrix, and then obtains an ABCD parameter of a de-embedded DUT using a matrix root-opening operation and an inverse matrix operation.