The Hard X-ray Telescope (HXT) is a Fourier-synthesis imager of 64 elements (each subcollimator measures a spatially-modulated incident photon counting rate). A set of photon count data from the 64 subcollimators is telemetered to the ground and synthesized there into an image through Fourier transform methods. The X-ray optics section consists of an assembly of tungsten grid plates 0.5 mm thick, arranged within a metering tube with transverse dimensions 417 mm x 376 mm and 1400 mm long. The metering tube is positioned between the Sun and a package of 64 detector modules with tranverse dimensions 465 mm x 392 mm and 223 mm deep. Each module consists of a NaI(T1) scintillation crystal (25 mm square) and a photomultiplier/ pre-amplifier. The effective sensitive area of the telescope is 70 cm**2. An electronics unit converts pulse-height analogue signals from the detector modules into digital signals and then counts the incident photon number after discriminating the photon energy into four energy bands with edges 15, 24, 35, 57 and 100 keV. Thus HXT will make the first solar flare imaging observations at energies above 30 keV. An image aspect system situated along the axis of the metering tube provides a white-light solar image which permits registration of the X-ray image. The field of view of each detector module encompasses the whole solar disk, and with the Maximum Entropy Method, the outputs of the 64 detectors may be combined to synthesize an image of a solar flare source anywhere on the solar disk. Angular resolution of approximately 5 arc s has been achieved. The first image data were acquired on Oct. 3, 1991, and more than 150 flares had been recorded by the end of Jan. 1992. The sensitivity of HXT is approximately 100 times that of its predecessor instrument of the Solar Maximum Mission spacecraft, and approximately 10 times the sensitivity of the X-ray imager aboard the Hinotori spacecraft. Movies of solar hard X-ray flares have been produced with satisfactory counting statistics at 2-s time resolution.