Objective Explore the value of clinical application of ultrasound attenuation coefficient (AC) in the quantitative diagnosis of non-alcoholic fatty liver disease (NAFLD). Methods Select a total of 120 subjects who had received abdominal CT examination and blood sampling in our hospital from Feb 2022 to Apr 2024 at random, and grade the severity of fatty liver according to the liver/spleen CT ratio (LSR), and relate N0, N1, N2, and N3 to the non-fatty liver, mild, moderate, and severe groups, respectively, each group including 30 subjects. Adopt acoustic attenuation imaging (ATI) to examine the AC value, meanwhile measure the AC value by sound attenuation imaging (ATI) technology to obtain the optimal cut-off values of different degrees of fatty liver.Analyze the correlation between AC and LSR, body mass index (BMI) and triglyceride (TG). Results There were statistically significant differences in AC, LSR, BMI, and TG among the groups (P<0.05), and the ROC curve analysis showed that the AC cut-off values of ≥ N1, ≥N2, and ≥N3 were 0.73, 0.80, and 0.88 dB/cm/MHz, respectively, and the corresponding sensitivities were 83.33%, 90%, and 96.67%, respectively. The corresponding specificities were 80%, 86.67% and 96.67%. AC values were positively correlated with LSR, BMI and TG. Conclusion The severity of non-alcoholic fatty liver disease was assessed non-invasively by ATI technique, and the hierarchies of diagnosis of AC was: N0<0.73 dB/cm/MHz; 0.73 dB/cm/MHz≤N1＜0.80 dB/cm/MHz；0.80 dB/cm/MHz≤N2＜0.88 dB/cm/MHz；N3≥0.88 dB/cm/MHz. It is intensively significant in guiding the follow-up and outpatient testing of patients.