In order to form a set of measurement system dedicated to the closed resonant cavity to replace the vector network analyzer, the spectrum analyzer module and the tracking generator module are adopted to control the system based on the C++ and VISA library functions and achieve the measurement function on the resonant frequency and the quality factor. Thereafter, the dielectric constant of the microwave dielectric material can be calculated, and a set of integrated closed cavity dielectric constant measuring system is formed. The system is employed to measure the microwave dielectric ceramic material K65 compared with the vector network analyzer. The relative error of the dielectric constant is 5.5×10-3, the relative error of tanδ is -3.74×10-2. When measuring material K35, the relative error of the dielectric constant is -1.69×10-3, and the relative error of tanδ is 1.08×10-1. The relative error of the dielectric constant is less than 0.01, and the relative error of tanδ is less than 0.5, indicating that the measurement results of the integrated dielectric constant measurement system are accurate. It can be used for the dielectric constant measurement by the closed cavity method, and can also be extended to other dielectric constant measurement systems.