The mudskipper Boleophthalmus pectinirostris is a commercially important fish in China. At present, this species is widely farmed in the southeastern coastal waters of China. Studies have been focused on early development and larval rearing. Early larval feeding habits have been documented. However, little is known about the digestive enzymes at the e arly stage of Boleophthalmus pectinirostris. The purpose of this study was to investigate the digestive enzyme activities of this species in ord er to know its nutritional requirements and establish the feeding protocols for optimizing larval mass rearing production. Changes of pancreatic, intestinal enzymes and pepsin activities in prelarva, postlarva, juvenile and early young fish of Boleophthalmus pectinirostris were investigated by means of enzyme analyses. In order to obtain pancreatic segment (PS) and intestinal segment (IS), juvenile and early young fish were cut into four parts: head, PS, IS and tail. The intestinal segments were homogenized to purify intestinal brush border membranes (BBM). The secretion levels of pancreatic enzymes were expressed as percentages of the segmental activity in the IS related to total activity (PS + IS). The establishment of an efficient intestinal BBM digestion represents the adult mode of digestion by enterocytes. And the degree of purified intestinal BBM was estimated by the enrichment factors and the activities of the intestinal enzymes. The results of this study show that the specific activities of four pancreatic enzymes (amylase，trypsin, chymotrypsin and carboxypeptidaseA) and eight intestinal enzymes (maltase, sucrase, luctase, trehalase, cellobiase, alkaline phosphatase, aminopeptidase and γ-glutamyltranspeptidase) are higher in the larval stage, decrease to the lowest levels in the juvenile stage, and increase rapidly in the early young stage. However, the total enzyme activit ies of individual increase with the development of larvae. Pepsin is initially detected in the postlarval stage, and then it continuously increases rapidly. The percentages of four pancreatic enzymes activities accounting for the total activities are significantly higher in the early young fish than in the juvenile in the intestinal segment. Only three enzymes (maltase, cellobiase and γ-glutamyltranspeptidase) are highly enriched in the intestinal brush bord er membranes in the juvenile. However, enrichment factors of seven intestinal enzymes in intestinal brush border membranes of the early young fish are all above 5.1 except for sucrase. In conclusion, in the larval stage, protein digestion depends on pancreatic enzymes; and when the larvae develope into the juvenile stage, pepsin plays an important role in protein digestion. The complete achievement of the secretion mechanisms of pancreas and maturation of enterocytes in the early young fish indicate the formation of an adult fish mode of digestion.