The study was conducted to determine the ultrasonographic features of the liver, gallbladder and spleen of 12 apparently healthy Philippine monitor lizards (Varanus marmoratus Weigmann, 1834) using an ultrasound machine equipped with a 5.0-MHz linear array scanner. The animals were grouped by size (four large and eight small) and sex (eight male and four female). The ultrasound appearance, dimensions and echo mean values of the liver, gall bladder and spleen were determined. The hepatic parenchyma showed a hypoechoic homogenous image with no distinct capsule. Anechoic longitudinal structure with hypoechoic wall representing the central hepatic vein was observed within the liver parenchyma. The gallbladder was recognized as a round or oblong anechoic structure found cranial to the spleen. The spleen was observed to be ovoid in shape and was markedly more echogenic than the liver. No significant differences in the measurements and echo mean values among sex and sizes were observed in the different organs, except for greater size of the liver in larger varanids compared to smaller ones. The results of the study could be used as basis for assessing disorders and diseases of monitor lizards.