Аннотация:An investigation was made of the pyroelectric and dielectric properties of barium nitrite monohydrate crystals. A domain structure was observed and it was found that this structure was altered by the application of a uniaxial mechanical load along the polar axis, i. e. , the axis along which the crystals exhibited pyroelectric properties. On application of a stress of approximately 6 kg/cm**2 the pyroelectric coefficient reached 70-80 cgs esu, which made this crystal promising for pyroelectric converters.