A high directivity millimetre-wave antenna based on woodpile electromagnetic bandgap (EBG) material at W-band is presented. The woodpile EBG structure is fabricated using the ceramic extrusion freeforming technique with high purity alumina powder. The designed antenna can achieve a narrow beam without using an array. The measured half power beam widths are 14 degrees and 10 degrees for E-plane and H-plane, respectively. Measurements results are good compared with simulations.