The wire antenna loaded with alumina was designed for the lower hybrid resonance heating in a small toroidal machine. The antenna impedance was calculated by the electromotive force method using the variational principle and found to be large enough to match with the r.f. source through usual transmission lines. The power spectrum was well behaved to satisfy the so-called accessibility condition in terms of the refractive index along the static magnetic field. Electron heating as well as ion heating is possible because the spectrum of radiated slow wave can be controlled by the selection of the thickness to the alumina cover. Alumina serves as an insulator against breakdown as well as a retarder of waves.