Objective: To evaluate the efficacy, establish a diagnostic model, and value of ultrasound attenuation parameters (UAP) to diagnose hepatic steatosis in metabolic dysfunction-associated fatty liver disease (MAFLD) and its relevant disorders. Methods: 3770 cases were selected from the Health Examination Center of the Third Hospital of Hebei Medical University between October to December 2020. MAFLD diagnosis was based on the Asia-Pacific region MAFLD clinical diagnosis and treatment guidelines. The degree of hepatic steatosis was divided into mild, moderate and severe according to ultrasound imaging. UAP, clinical characteristic indexes, serum biochemical indexes, characteristics of hepatic steatosis and related factors were compared and analyzed in MAFLD patients and healthy controls. Logistic regression method was used to analyze the independent risk factors affecting the progression of hepatic steatosis in MAFLD to establish the diagnostic model. The clinical efficacy of UAP and the new model in diagnosing MAFLD was evaluated by the receiver operating characteristic curve (ROC). One-way ANOVA was used to compare means among multiple groups. Mann-Whitney U test was used to compare non-normally distributed measurement data between the two groups, and rank-sum test was used to compare multiple groups. χ 2 Among the 3 770 cases, 650 were MAFLD, with a prevalence rate of 17.24%, and the highest prevalence was 37.23% in the age group of 60-69. The prevalence rate was significantly higher in male than female (30.34% vs. 9.17%). Age-sex analysis showed that the prevalence rate in males aged 30-69 years was 38.26%, and that in females aged over 60 years was 31.94%. UAP was significantly higher in patients with MAFLD than healthy controls (278.55 dB/m vs. 220.90 dB/m, Results: Among the 3 770 cases, 650 were MAFLD, with a prevalence rate of 17.24%, and the highest prevalence was 37.23% in the age group of 60-69. The prevalence rate was significantly higher in male than female (30.34% vs. 9.17%). Age-sex analysis showed that the prevalence rate in males aged 30-69 years was 38.26%, and that in females aged over 60 years was 31.94%. UAP was significantly higher in patients with MAFLD than healthy controls (278.55 dB/m vs. 220.90 dB/m, Z ＜0.001), and an increasing trend with increased degree of hepatic steatosis (mild:257.20 dB/m, moderate:286.20 dB/m, and severe: 315.00 dB/m) were observed. The cut-off values of UAP for the diagnosis of mild, moderate and severe hepatic steatosis were 243≤UAP＜258 dB/m, 258≤UAP＜293 dB/m, ≥293 dB/m in MAFLD. The sensitivity and specificity were 67.20%, 93.60%, 95.90%, and 82.10%, 72.00%, and 84.80%, respectively. UAP, alanine aminotransferase and fasting blood glucose were independent risk factors for the progression of hepatic steatosis in MAFLD. The combined MAFLD classification model (UAG model) was established. The AUC of mild, moderate and severe hepatic steatosis in MAFLD were 0.906, 0.907, and 0.946, respectively, and the sensitivity and specificity were 76.50%, 82.10%, 98.00%, and 90.80%, 83.30% and 76.10%, respectively. P ＜0.001), and an increasing trend with increased degree of hepatic steatosis (mild:257.20 dB/m, moderate:286.20 dB/m, and severe: 315.00 dB/m) were observed. The cut-off values of UAP for the diagnosis of mild, moderate and severe hepatic steatosis were 243≤UAP＜258 dB/m, 258≤UAP＜293 dB/m, ≥293 dB/m in MAFLD. The sensitivity and specificity were 67.20%, 93.60%, 95.90%, and 82.10%, 72.00%, and 84.80%, respectively. UAP, alanine aminotransferase and fasting blood glucose were independent risk factors for the progression of hepatic steatosis in MAFLD. The combined MAFLD classification model (UAG model) was established. The AUC of mild, moderate and severe hepatic steatosis in MAFLD were 0.906, 0.907, and 0.946, respectively, and the sensitivity and specificity were 76.50%, 82.10%, 98.00%, and 90.80%, 83.30% and 76.10%, respectively. Conclusion: MAFLD is a common disease in the general population, with a higher incidence in male and elderly female over 30 years of age. UAP can be used as a new noninvasive diagnostic technique to evaluate hepatic steatosis in MAFLD. The UAG model has a good diagnostic efficacy on MAFLD and its relevant disorders, and thus can be used as a guide for evaluating clinical diagnosis and prognosis.