Penelitian ini bertujuan untuk mempelajari morfologi dan histologis esofagus, lambung dan usus belut (Monopterus albus). Pengamatan dilakukan secara makroskopis dan mikroskopis menggunakan tiga ekor belut. Secara makroskopis belut diamati dan diukur panjang tubuh, berat tubuh dan panjang saluran pencernaan. Esofagus, lambung dan usus dibuat menjadi preparat histologi menggunakan pewarnaan Hematoksilin-Eosin (HE) dan diamati di bawah mikroskop. Rata-rata panjang total tubuh belut 43,6 cm, berat tubuh rata-rata 53,9 g dan panjang saluran pencernaan rata-rata 23 cm yang merupakan belut dalam fase interseks. Esofagus terdapat di bagian belakang rongga mulut berbentuk tabung panjang yang menyempit dibagian ujungnya. Lambung terdiri dari bagian kardiak, fundus dan pilorus. Usus terbagi menjadi menjadi dua segmen yaitu usus proksimal dan distal. Histologis esofagus, lambung dan usus sama seperti ikan umumnya terdiri dari empat lapisan yaitu tunika mukosa, tunika submukosa, tunika muskularis dan tunika serosa. Tunika mukosa esofagus terdapat sel goblet berukuran besar. Lambung memiliki tunika muskularis yang tebal. Tunika mukosa usus memiliki lipatan vili panjang menuju lumen. Tunika mukosa esofagus belut berbeda dengan ikan umumnya yaitu terdiri dari epitel silindris selapis. (This research aimed to study the morphological and histological of esophagus, stomach, and intestine of eel (Monopterus albus). The observations were done macroscopic and microscopic by using three eels. Macroscopic the eel was observed and measured the body length, the body weight and the length of the gastrointestinal tract. The esophagus, stomach, and intestine were made into histologic preparations using Hematoxylin-Eosin (HE) staining and observed under a microscope. The average total length of the eel body was 43.6 cm, the mean body weight was 53.9 g and the average gastrointestinal length was 23 cm which was indicated the eel in the intersex phase. The esophagus was located at the back of the long tubular cavity narrowed at the end. The stomach consisted of cardiac, fundus and pylorus. The intestine was divided into two segments the proximal and distal colon. The Histology of esophagus, stomach, and intestine was similar with histology of fish that generally consist of four layers, i.e. mucosal tunica, submucosal tunica, muscular tunic and serous tunica. There was a large goblet cell in the tunica mucosa of the esophagus. The stomach had a thick muscularis tunica. The tunica mucosa of intestine had a long fold of villi to the lumen. Tunica mucosa of eel’s esophagus was different from the fish that generally consist of a cylindrical epithelial layer.)