β-endorphin is a kind of brain-gut peptide and plays important physiological roles. The distributive patterns of β-endorphin in the digestive tract and brain of Schizothorax prenanti were studied using strept avidin-biotin complex (SABC) immunocytochemical method. β-endorphin-positive cells were observed through Olympus microscope and the number and optical density of β-endorphin-positive cells were measured using image analysis software and expressed as Mean ± standard deviations. The results showed that the positive immunoreactions presented brown yellow color (Plate I: 1-14), while negative control in the foregut showed only hematoxylin staining (Plate I: 15). There was no β-endorphin-positive reaction in the esophagus or hindgut. β-endorphin-positive cells were detected in the oropharyngeal cavity (Plate I: 1), foregut (Plate I: 2) and midgut (Plate I: 3), presenting various kinds of forms, such as round, ovoid, tadpole, spindle and cone shapes. The density of β-endorphin-positive cells in the digestive tract was the highest in the foregut (13.10 ± 4.50 number/mm2), medium in the midgut (10.08 ± 2.96 number/mm2) and the lowest in the oropharyngeal cavity (8.52 ± 3.72 number/mm2) (Table 1). β-endorphin-positive reaction was located in the neurons of diencephalon (Plate I: 4-9), mesencephalon (Plate I: 11-13) and metencephalon (Plate I: 14), and the nerve fibers of mesencephalon (Plate I: 10). The density of β-endorphin-positive neurons in the brain was the highest in the eminentia medialis (248.42 ± 84.25 number/mm2), medium in the nucleus anterior tuberis of medium lobe of hypothalamus (150.42 ± 15.08 number/mm2) and inferiors lobes of hypothalamus (141.80 ± 45.36 number/mm2), lower in the nucleus geniculatus lateralis (98.44 ± 28.34 number/mm2), nucleus prerotundus (86.21 ± 18.45 number/mm2), nucleus subrotundus (92.81 ± 11.19 number/mm2), side of fasciculus longitudinalis medialis (95.10 ± 8.23 number/mm2) and layer of purkinje cells of cerebella valvula (88.73 ± 41.20 number/mm2), and the lowest in the corpus mammillare of inferiors lobes of hypothalamus (60.72 ± 10.39 number/mm2) and upper area of tegmentum (47.27 ± 11.95 number/mm2) (Table 1). The distribution patterns of β-endorphin-positive cells in the digestive tract of Sehizothorax prenanti are greatly related to its feeding habits, intestinal functions and structures as well. The distributive characteristics of β-endorphin-positive cells in the brain may be relevant to neuroendocrine activities in different areas of the brain. β-endorphin was widely distributed in the digestive tract and brain of Schizothorax prenanti, further suggesting that this molecular is a kind of brain-gut peptide. This study provided morphological evidence for regulating digestive and neuroendocrine activities by β-endorphin.