This apparatus for producing a hyperpolarized noble gas includes: a hyperpolarized noble gas generating cell in which a noble gas is subjected to an optical pumping in the presence of an alkali metal so as to generate a hyperpolarized noble gas; and a very fine capillary tube having an inside diameter of 0.1 to 1.25 mm which is positioned downstream from the hyperpolarized noble gas generating cell. This nuclear magnetic resonance spectrometer includes the above apparatus for producing a hyperpolarized noble gas and a nuclear magnetic resonance measuring instrument. This magnetic resonance imager includes the above apparatus for producing a hyperpolarized noble gas and a magnetic resonance image measuring instrument.