The formation of atherosclerotic plaque is the main mechanism of coronary heart disease. The instability of plaque is significantly related to the occurrence of acute coronary syndrome. At present, the detection of plaque instability is mainly through intravascular ultrasound, optical coherence tomography and other invasive operations. The microRNA, apelin, galectin-3, endocan and other serological indicators are directly related to the stability of plaques, which can be used as biological indicators to predict the stability of plaques. This article reviews the research progress on the relationship between microRNA, apelin, galectin-3, endocan and atherosclerotic plaque stability.