From 18 to 21, February 2022, the technical team of Biogas Technology and Information Center (BTIC) conducted the field monitoring to assess the efficiency of commercial biogas treatment systems in M’s pig II located in Prey Nob, Preah Sihanoukville. During this mission, the team measured the gas quality before and after desulfurizing units and discussed on issues and found the solution to smoothly operate the system. In term of gas measurement, the methane content (CH4) before and after pretreatment units was non-significant with amount of 70% whereas, the H2S concentration was 5000 ppm before pretreatment units and its amount was reduced to 11 ppm after desulfurizing units under allowable standard of genset operation. Noted that based on the supplier’s instruction, the iron pellets will be replaced monthly for full operation.