Techniques for defining a damascene gate in nanowire FET devices are provided. In one aspect, a method of fabricating a FET device is provided including the following steps. A SOI wafer is provided having a SOI layer over a BOX. Nanowires and pads are patterned in the SOI layer in a ladder-like configuration. The BOX is recessed under the nanowires. A patternable dielectric dummy gate(s) is formed over the recessed BOX and surrounding a portion of each of the nanowires. A CMP stop layer is deposited over the dummy gate(s) and the source and drain regions. A dielectric film is deposited over the CMP stop layer. The dielectric film is planarized using CMP to expose the dummy gate(s). The dummy gate(s) is at least partially removed so as to release the nanowires in a channel region. The dummy gate(s) is replaced with a gate conductor material.