Carcasses of pigs were trench buried using either general soil or mature compost as a cover material and the malodorous substances discharged were observed about a year. With the soil burial method, the speed of decay was shown to be dominantly affected by the ambient air temperature. However the compost burial method’s decaying process took place quickly, even ambient air temperature was dropped; it holds the temperature of 40oC or higher. With the compost burial method, there was a period where, the temperature inside the pig carcasses and the temperature of cover-material layer were strongly reversed. From this discovery, level of decay process could be speculated. With the soil burial method there was a trend when malodorous substances concentration was high, the level of concentration in the cover soil was also tends to be high. However, the compost burial method had different result. When malodorous substances concentration was high the level of concentration in the compost cover layer was observed to be lower. This indicates compost burial method shown to intercept and absorb malodorous substances. Furthermore, the compost burial method appears to be able to contribute to deactivate the pathogens by quickly decompose the carcasses at a high temperature.