The corrosion of biogas pipes and equipments damage as generators, boilers and coprocessors is one of the most real important problems in Damascus wastewater treatment plant (at Adra region). These problem caused high financial losses and costs , that it required studying and solving. Biogas is the result of an aerobic digestion process of sludge, it contains about 50-70% of methane as a main resource of power, where the biogas considers free when it release spontaneity. Different analysis have been occurred on the biogas to show its components, tests on the pipes material and analysis of sediment material inside the pipes that caused by biogas.