BACKGROUND Chitinases have been widely studied and can be produced by various groups of microorganisms, in particular, marine bacteria. The exploration of extremophilic marine microorganisms bears advantageous and unique biotechnological implications and the scaling up of the production process is a decisive stage to be researched. RESULTS A chitinase gene from Halobacterium salinarum was expressed in Escherichia coli and the protein production process was performed at different scales. In order to determine the most suitable bioreactor, two configurations were investigated: stirred‐tank and airlift. It was demonstrated that the stirred‐tank configuration led to the highest chitinase activities. The effect of stirrer speed (range 150–400 rpm) and aeration rate (range 0.6–2 vvm) was investigated, and maximum activity levels of 20.99 U L‐1 were detected at 300 rpm and 0.66 vvm CONCLUSION Chitinase from H. salinarum expressed in E. coli was successfully produced in a mechanically stirred bioreactor, and the optimum conditions of agitation and aeration were ascertained. The chitinase obtained turned out to possess a mass weight of 66 kDa, as determined by SDS‐PAGE. The system was suitably characterized with known mathematical models. © 2013 Society of Chemical Industry