OBJECTIVE: This study aims to investigate the diagnostic potential of bile acid profiles combined with lipid parameters in metabolic dysfunction-associated steatotic liver disease (MASLD). METHOD: This study employed LC-MS technology to analyze the serum bile acid profiles of 186 male patients with MASLD and 80 male non-MASLD patients. According to whether the serum samples exhibit dyslipidemia, the subjects were divided into four groups. Subsequently, a series of analyses were conducted, including univariate analysis, the Spearman correlation test, multinomial logistic regression, restricted cubic spline regression, and ROC curve analysis. RESULT: The bile acid profiles of serum samples with dyslipidemia exhibit significant differences compared to those of normal serum samples. The bile acids, which include total deoxycholic acid (DCA), secondary bile acids (SBA), unconjugated bile acids (UCBA), 12α-hydroxylated bile acids (12HBA), total bile acids (TBA), primary bile acids (PBA)/SBA, and glycine-conjugated bile acids (GCBA)/taurine-conjugated bile acids (TCBA), demonstrate a non-linear correlation with the logarithmic ratio of triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C). The ROC analysis indicates that, in populations with normal lipid levels, bile acid indicators such as GLCA and 12HBA demonstrate a superior ability to distinguish between MASLD and non-MASLD compared to populations with abnormal lipid levels and the overall population. Their diagnostic performance significantly surpasses that of existing MASLD diagnostic models. CONCLUSION: The combination of bile acid profiles and lipid indicators holds significant diagnostic potential in MASLD.