This work purposed to investigate alkaline proteases from the marine shrimp (Farfantepenaeus paulensis). This research could prove to be a relevant source of information for the understanding of the digestive physiology of these shrimps. The hepatopancreas were homogenized with 0.9% (w/v) NaCl (40 mg/mL) using a tissue homogenizer and centrifuged at 10,000xg at 4°C for 25 minutes. Specific proteolytic activity was determined using benzoyl-arginine-p-nitroanilide (BApNA) and leucine-p-nitroanilide (Leu-p-Nan). For enzyme inhibition phenyl-methyl-sulfonil-fluoride (PMSF), tosyl-lysine chloromethyl ketone (TLCK), benzamidine, and bestatin were used as specific inhibitors. The proteolytic patterns were observed using 3% casein as substrate in thermal stability zymograms. The specific proteolytic activity of crude extract was 7.25 mU/mL and 0.20 mU/mL when BapNA and Leu-p-Nan were used, respectively. Inhibition of the crude extract of F. paulensis rendered different results, owing to the diverse proteases present on this preparation. The highest inhibitions were obtained when TLCK (86.13%) and benzamidine (89.94%) were used. PMSF was capable to inhibit 47.28% of the proteolytic activity. Seven bands were observed in the zymogram of the crude extract of F. paulensis. The thermal stability zymogram showed that one band remained active after incubation of 30 minutes at 85ºC. The results suggest that trypsin and leucine aminopeptidase are present in Farfantepenaeus paulensis hepatopancreas. In addition to that one enzyme presents a high thermal stability at extreme conditions of temperature.