Chitin is after cellulose the second most abundant biopolymer on earth. It's production is enormous and it's degradation is especially in the oceans an important step to ensure the continuous availability of carbon and nitrogen. One very important enzyme found in the chitin biodegradation pathways of bacteria, fungi and archaea is the chitinase. Within this study a novel three step chitinase test panel was established and tested, consisting of isolation and cultivation of microorganisms on chitin as sole carbon and nitrogen source, the molecular screening of the cultivated strains and the evaluation of the respective chitinase activity. This approach was used to investigate a total of 145 bacteria isolated from different marine microbial communities and strain collections. Furthermore the test panel was used to detect and describe the first crenarchaeal chitinase from Sulfolobus tokodaii and the chitinase of the halophilic euryarchaeon Halobacterium salinarum after expression in E. coli.