Objective: Aims were to examine associations (1) between non-alcoholic fatty liver disease (NAFLD) and the presence and severity of coronary artery disease (CAD) and obesity, (2) between CAD and NAFLD with aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma glutamiltransferase (GGT) levels. Materials and Methods: In this cross-sectional study, the study group consisted of 355 patients (mean age: 57.5±11.4 years), that comply with inclusion criteria and selected of 414 consecutive patients who underwent coronary angiographies. Coronary artery disease was defined as a stenosis at least 50% in at least one major coronary artery. Modified Gensini scoring was used to determine the severity of coronary atherosclerosis. Fatty liver was diagnosed by abdominal ultrasonography (4 stages: Grades 0, 1, 2 and 3). Obesity was defined as body mass index (BMI)≥30 kg/m2. Statistical evaluations were performed using Student’s t test, ANOVA, Chi- square, kappa tests and logistic regression analysis. Results: There were significant differences among Grades 0, 1 and 2-3 according to presence of CAD and Gensini score. In univariate analysis, age (OR=1.03, p=0.004), gender (OR=3.05, p<0.0001), dyslipidemia (OR=4.40, p<0.0001), diabetes mellitus (OR=2.15, p=0.048), smoking (OR=3.19, p<0.0001), AST (OR=1.01, p=0.042), GGT (OR=1.04, p<0.0001), NAFLD (OR=1.87, p=0.036) and obesity+NAFLD (OR: 2.1, p=0.018) have effects on presence of CAD. In multivariate model, age (OR=1.04, p<0.001), AST (OR=1.01, p<0.05), GGT (OR=1.04, p<0.001), NAFLD (OR=2.58, p<0.01) have independent effects on CAD; however BMI and obesity were ineffective. Non-alcoholic fatty liver disease has an independent effect on Gensini score (OR=2.02, p<0.05). Conclusions: Ultrasonographic fatty liver have independent effects on both the presence of CAD and severity of coronary atherosclerosis. In addition, increased serum AST and GGT levels may be independently associated with CAD.