Abstract: The contents of cyanogenic glycosides (Cyanogenic Glycosides, CNGs) are very important to evaluate the safety of sweet cassava roots and their products. Using cassava roots and cassava products as test materials in this study, a method for rapid extraction and high performance liquid chromatography-evaporative light scattering (HPLC-ELSD) detection of two kinds of cyanogenic glycosides was established. The content of CNGs in different varieties of cassava roots, cassava flour, and their products were analyzed. The results showed that the optimal extraction concentrations of sulfuric acid solution for these two GNSs from cassava roots and flour were 0.025 and 0.100 mol/L, respectively. The HPLC-ELSD method was effective in the separation of linamarin and lotaustralin. The linear correlation was good in the range of 4.1 to 820.0 mg/L and 2.5 to 250.0 mg/L, which correlation coefficients (r) reached 0.9996 and 0.9993 respectively. The LOD was 2.1 and 0.5 mg/L, and the LOQ was 8.2 and 2.0 mg/kg, respectively. The relative standard deviation (RSD) of repeatability and sample stability are both less than 5.0%. The average recovery rates of two CNGs in cassava roots and cassava products were between 89.3%~96.3% and 107.5%~114.9%, respectively. And the RSD of the repeatability of the recovery was less than 3.4%. The results of sample verification showed that the content of CNGs in different cassava varieties were quite different, The content of CNGs was lower in cassava flour which was prepared from cassava grown for 8~9 months, and the cooking method could effectively remove CNGs in cassava food. This method was simple, stable and accurate, and had a strong application prospect in the analysis and evaluation of CNGs in sweet cassava roots and their products.