A metamaterial-based permittivity and thickness sensor structure for dielectric substrate material has been proposed at the X band frequency regime. The sensor structure is designed by using a split meander line type resonator and examining it both numerically and experimentally. Various types of dielectric substrate samples have been used to verify the precise sensing characteristics of the proposed sensor. The sensor layer has been chosen as the back side of the sensor structure, and the reflection frequency of the incident signal has been examined The sensor layer thickness has been varied from 0.4 mm to 1.6 mm for the thickness sensing study with two different types of dielectric substrate having the same electromagnetic characteristics. The permittivity sensing study has been carried out by several dielectric materials which have permittivity values between 10.20 and 1.96. The proposed sensor structure can be effectively used in many application areas such as microwave material design, the defense industry and in medical devices.