Introduction: Several researchers focused on the role of skeletal muscle in metabolic problems in recent years. We aimed to evaluate influence of sleeve gastrectomy on skeletal muscular fat infiltration determined by magnetic resonance imaging in patients with metabolic syndrome (MetS).Methods: 65 MetS patients (male/female 20/45; mean age, 35.3 years +/- 6.7 [standard deviation]; age range, 22 - 59 years) enrolled in our study. Prior to and one year after sleeve gastrectomy, patients underwent routine measurement of skeletal muscular fat concentration (denoted by proton density fat fraction, PDFF) and chemical indexes. The associations of skeletal muscular fat concentration with other variables were determined using multiple backward linear regression analysis.Results: Difference between skeletal muscular PDFF at baseline (4.25 +/- 2.05 %) and PDFF one-year after sleeve gastrectomy (2.91 +/- 1.54 %) was significant. Multivariable predictors of baseline skeletal muscular PDFF by descending order of standardized coefficient were fasting serum insulin (0.477; P = 0.001), fasting serum glucose (0.473; P < 0.001), age (0.396; P < 0.001), systolic pressure (0.334; P = 0.020), white cell count (0.235; P = 0.031), diastolic pressure (-0.295; P = 0.047), C-peptide (-0.309; P = 0.022), and alkaline phosphatase (-0.481; P < 0.001) all at baseline. Furthermore, multivariable predictors of change in PDFF were serum total cholesterol (3.514; P < 0.001), alkaline phosphatase (0.538; P < 0.001), estrogen (0.458; P < 0.001), diastolic pressure (0.355; P < 0.001), systolic pressure (-0.409; P < 0.001), high-density lipoprotein cholesterol (-0.719; P < 0.001), insulin (-0.775; P < 0.001), C-reactive protein (-0.902; P < 0.001), triglyceride (-1.758; P < 0.001), and low-density lipoprotein cholesterol (-2.858; P < 0.001) all at baseline.Discussion/Conclusion: Sleeve gastrectomy could alleviate myosteatosis in MetS patients during one-year follow-up. The extent of remission on skeletal muscular fat infiltration after sleeve gastrectomy was influenced by baseline metabolic problems related to serum glucose, serum lipid, and blood pressure level.