讨论了最近在韩国国防开发局（ＡＤＤ）固体火箭发动机研制项目中遇到的燃烧不稳定现象。在研制少烟推进剂火箭发动机时，发生了燃烧不稳定现象，即不规则燃烧。通过对试车台点火试验时记录下的加速度计信号和应变传感器信号进行频谱分析以及用分析系统对发动机内腔进行的声摸分析，发现不稳定性为二次切向振型。 Discussed the recent instability of combustion encountered in the development of the Solid State Rocket Engine at the Korea Defense Development Agency (ADD). In the development of less smoke propellant rocket engine, the phenomenon of combustion instability, that is, irregular combustion. By analyzing the accelerometer signal and strain sensor signal recorded by the test rig during the ignition test and analyzing the acoustic dynamics of the engine cavity with the analysis system, we found that the instability is the secondary tangential vibration mode.