CsDNBF (cesium 7-hydroxy-4,6-dinitro-5,7-dihydrobenzofur-oxanide) was synthesized from the sodium salt of DNBF and cesium nitrate. ne thermal decomposition process has been investigated and the results show that the solid residues at 240 degrees C are RCOOCs, CsNCO, RNO2 and CsNO3. The sensitivity results demonstrate that CsDNBF has better properties than KDNBF, which has been widely used.