Chitin from shrimp shells was prepared to evaluate the production of extracellular chitinase from Serratia marcescens QM B1466 in submerged culture under controlled conditions of temperature (28°C). shaking (150 rpm) and pH (7.7).To determine the composition of chitin on the shell, the material was ground, classified by sieving, deproteinized and demineralized. The proximate waste analysis indicates a high content of crude protein (36.11%). The highest chitinase activity during the enzymatic hydrolysis process was 1.91 µmols. equivalent to N-actetylglucosamine produced per mi of filtered culture: this determines the enzyme capacity of hydrolysis on the crystalline chitin. The percentage of chitin conversion during fermentation (73%) is the result of this activity. The N-acetylglucosamine produced is used by the bacterium for growth. which was adjusted to the Monod model.