Objectives The primary aim of this study was to evaluate the histological adequacy of the liver tissue specimens obtained with a 20-gauge fine-needle biopsy needle and the secondary aim was to test the safety endoscopic ultrasound-guided liver biopsy with a 20-gauge fine-needle biopsy needle with the wet-heparinized suction technique. Methods Forty patients who underwent endoscopic ultrasound-guided liver biopsy were included in the study. A 20-gauge fine-needle biopsy needle was used with the wet-heparinized suction technique to make one pass each from the left and the right lobe. Histologic characteristics of the specimens were evaluated, and patients were observed after the procedure in order to intervene in case of an adverse event. Results The median longest core fragment was 22 mm from the left lobe [first quartile-third quartile 20-25 mm, interquartile range (IQR) 5 mm], and 20 mm (first quartile-third quartile 17-22 mm, IQR 5 mm) from the right lobe. The median cumulative core length per patient was 103 mm (91-108 mm, IQR 17 mm). The median cumulative number of complete portal triads per patient was 69.50 (52.25-82.25, IQR 30). The rate of diagnostic yield was 100%. Post-biopsy self-limiting abdominal pain was reported in two patients (5%). The most common histologic diagnosis was fatty liver disease (25%). Conclusion Endoscopic ultrasound-guided liver biopsy with the wet-heparinized suction technique using a 20-gauge fine-needle biopsy needle is a safe alternative method in clinical practice.