Construction, controlling, and data processing system of a 3 dimensional spectro-gonioreflectometer developed at National Institute of Metrology (NIM) are introduced in this paper. Radiance uniformity of a spherical radiator and photometric nonline-arity of measuring system as well as wavelength accuracy and stray radiation of the monochromator are tested. Reflected radiance distribution curves of a mat ceramic plate and a Halon pressed powder plate have been measured. Some inportant applications of the gonioreflectometor to colorimetry and spectro-photometry are discussed.