In 20 m3 smoke chamber,the jamming effects of 30 g nanometer crystalline titanium nitride（nano-TiN）smoke are tested.Tests are done not only to 1.06 μm and 10.6 μm laser but also to 3～5 μm and 8～12 μm IR.The experimental results show that nano-TiN smoke exhibits excellent extinction ability to broadband IR radiation and the mass extinction coefficients are all above 1 m2·g-1.Compared with the smoke performance of conventional materials （such as HC,RP,oil,graphite,carbon black）,nano-TiN smoke possesses better obscuration capability.Therefore,it is a new obscurant material which can effectively jam the broadband IR devices including 1.06 μm,10.6 μm,3～5 μm and 8～12 μm.