Purpose: Serum uric acid to creatinine ratio (SUA/Cr) has been associated with an increased risk of metabolic syndrome; however, limited evidence exists regarding the relationship between SUA/Cr and metabolic-associated fatty liver disease (MAFLD). This study aims to investigate the association between SUA/Cr, TyG-BMI (triglyceride glucose-body mass index), and MAFLD in Chinese adults. Patients and Methods: The data were obtained from a health examination conducted at Nanping First Hospital. Spearman correlation analysis was employed to assess the association between SUA/Cr or TyG-BMI and various risk factors pertinent to MAFLD. A multivariate logistic regression model was utilized to investigate the relationship between SUA/Cr or TyG-BMI and MAFLD. Additionally, restricted cubic splines (RCS) and receiver operating characteristic (ROC) curve analyses were applied to explore the relationship between SUA/Cr and MAFLD. Mediation models were constructed to figure out the mediating role of TyGBMI in the association between SUA/Cr and MAFLD. Results: Spearman correlation analysis showed a significant association between SUA/Cr and multiple risk factors for MAFLD (such as BMI, SBP, DBP, TG, TC, ALT, AST, GGT, FPG, and HDL). Furthermore, SUA/Cr had a positive correlation with TyG-BMI (P<0.05). The logistic model demonstrated that elevated levels of SUA/Cr were significantly associated with an increased risk of MAFLD, even after adjusting for confounding factors (odds ratio [OR]: 1.390; 95% confidence interval [CI]: 1.255-1.538). The RCS curves revealed a consistent and monotonic increase in the relationship between SUA/Cr levels and the occurrence of MAFLD. Moreover, SUA/Cr exhibited moderate discriminatory ability in identifying individuals with MAFLD (AUC: 0.669). Mediation analysis indicated that approximately 52.05% of the positive association between SUA/Cr and MAFLD was mediated by TyG-BMI. Conclusion: Our findings suggest a substantial association between elevated levels of SUA/Cr and an increased risk of MAFLD in the Chinese adult population, with TyG-BMI mediating this correlation.