L-carnitine administration was reported to improve sarcopenia in patients with cirrhosis. However, the amount of evidence from previous studies is not sufficient. The present study aimed to clarify the effect of levocarnitine (L-carnitine) administration on body composition in patients with chronic liver disease (CLD). In the present study, 85 patients with L-carnitine administration and 87 control patients were enrolled and divided them into two groups, the L-carnitine administration group (LAG, n=44) and the without L-carnitine administration (controls, n=44) group, by using propensity score matching for age, sex, body mass index (BMI) and serum albumin. Δ skeletal muscle mass index (SMI)/year, Δ intramuscular adipose tissue content (IMAC)/year and Δ bone mineral density (BMD)/year were examined during L-carnitine administration. Each parameter was measured by computed tomography (CT) or dual-energy X-ray absorptiometry. The median age overall was 69 years (IQR, 64.0, 75.0); 36 were men and 52 were women. The median SMI was 37.4 cm
2
/m
2
(IQR, 34.01, 44.34). The initial CT scans showed similar median values of SMI for the two groups [37.74 (34.17, 43.58) and 37.16 (33.83, 44.34), P=0.67]. However, the median ΔSMI/year for the LAG and controls were 0.95% (-3.07, 6.10) and -2.34% (-5.34, 0.53), respectively (P=0.003). The median Δ whole body BMD/year for the LAG and controls were -0.24% (-1.20, 0.91) and -1.04% (-2.16, 0.47), respectively (P=0.038). The median ΔIMAC/year and Δ lumbar spine BMD were not significantly different between the LAG and controls. L-carnitine administration may prevent the loss of skeletal muscle mass and BMD; therefore, it may be used as a new treatment option for osteoporosis and sarcopenia in patients with CLD.