The development of recombinant DNA has made it feasible to produce a wide range of valuable protein products in the bacterium Escherichia coli. Extraction of intracellular protein from E. coli is traditionally achieved by mechanical, chemical or enzymatic disruption technology. In this study, thermolysis, which differs from the traditional ones, is presented for disruption of E. coli cells to release recombinant thermostable enzyme. Heat treatment of E. coli at 80℃ is highly effective to destroy the integrity of the bacterial cell wall and release the recombinant thermostable enzyme. At the same time of disruption, the recombinant thermostable enzyme was partially purified. Moreover, thermolysis was carried out in fermentation broth in situ, which may make it a more applicable approach for industrial-scale processes.