Résumé : This chapter deals with deleterious effect on industrial machinery and other material structure due to Microbial Induced Corrosion. Corrosion, due to only chemicals, weakens the material strength prematurely and thus results in unscheduled shutdown of plants, catastrophic failure pf machinery, leakage of chemicals etc. This needs maintenance of machinery or its replacement. Other factors are also involved which together results in extra expenditure on industry to keep the system operational. This is Corrosion cost and it affects the economy of industrial production. Similar effect is also observed with MIC. The chapter discusses various aspects related to failure of machinery and the extent to which MIC is observed in various industries or structures etc. Although, it has not been possible to systematically evaluate damage due to MIC due to reasons e.g. (i) difficult to identify whether failure is due to corrosion or MIC or (ii) combining the effect of biocorrosion with biofouling etc. Still effort has been made to put an estimated cost due to MIC on the basis of data present in literature on MIC. An account of various industries and their various sections experiencing MIC has been given which helps in appreciating the deleterious effect of MIC on machinery, vehicles and structures etc.