Measured and simulated data supporting the publication “High-Q 100 GHz Photonic Crystal Resonator Fabricated from a Cyclic Olefin Copolymer” is provided. The S-parameter measurements were performed using a Keysight PNA-X N5247B vector network analyzer with Keysight N5295AX03 frequency extension modules and coaxial to waveguide adaptors. Full-wave electromagnetic simulations were performed using the finite-element method (FEM) solver in CST Microwave Studio.